HTGuide Forum - Dayton RS WMTW Center & TMWW Mains

Dennis Murphy

09-04-2006, 05:46 PM

This is just a general comment, not a reply to your post. For what it's worth, I actually used 15 Ga Jantz except for the big woofer coil. I wouldn't sweat small differences in dcr. On a different topic, I finished a promising crossover for the Seas center channel and listened to it on the emulator today. Now I have to build the board--a major pain. But I'm pretty sure the final version will differ only in the tweeter padding.

chasw98

09-04-2006, 06:19 PM

On a different topic, I finished a promising crossover for the Seas center channel and listened to it on the emulator today. Now I have to build the board--a major pain. But I'm pretty sure the final version will differ only in the tweeter padding.

Send me the schematic. I will build it for you and ship it out to you if you would like.

Chuck

Dennis Murphy

09-04-2006, 07:44 PM

Hi I appreciate the offer, but unless you plan on using this crossover, I can cobble something together.

chasw98

09-04-2006, 08:04 PM

Dennis, I am going to build it when you are done with the final version. I already have an H1212 waiting to use in place of the RS28 I am temporarily using. Besides that, it would be serial number 1!

Dennis Murphy

09-04-2006, 08:54 PM

Well, it would save me a lot of time. I'll send you the schematic. I've pretty much kept everything the same except the tweeter circuit. Thanks! (And, of course, I'll send it back.)

chasw98

09-04-2006, 09:09 PM

No problem. Glad to help.

ifeliciano

09-04-2006, 10:09 PM

Actual assembly has begun on my box style enclosure!

:D

Got clamps?

http://jonathanb3478.tripod.com/images/speaker/construction/gotclamps.jpg

What's the butter knife for ? :B

jonathanb3478

09-05-2006, 01:36 AM

What's the butter knife for ? :B

You don't like my excess glue scraper? You think I should have bought a uni-tasker? I hate uni-taskers.

:D

ifeliciano

09-05-2006, 09:40 AM

You don't like my excess glue scraper? You think I should have bought a uni-tasker? I hate uni-taskers.

:D

Well Duh ! I could not make out the glue scraping edge on the tool :D
Keep up the good work and more pics when you can Jonathan. :T

cobbpa

09-05-2006, 03:39 PM

Dennis..not to hassle you or anything as I hope you're busy with designing & such. ;-)

But could you give a clue as to whether the parts count for the Seas-based center will have a lower, similar, or higher parts count (price) than the Dayton schematic? I'm just trying to get a feel for cost as I'm planning some things, and obviously patience is not something I'm strong with..just curious!

dynamowhum

09-05-2006, 08:26 PM

Got my Center channel box cut up today. Will start glue up Thursday. Hopefully my cap will be in from PE tomorrow.
I am going to show my lack of tech savy here. Last year my digital camera got stolen at my daughters wedding. Yes all my personal pictures of my daugthers wedding went with it. Anyway I was wondering if you could some how download cell phone pics to the site. I guess even if you could the resolution wouldn't be that good. You guys have a good one.

ThomasW

09-05-2006, 09:07 PM

Pictures must be on a computer, then the forum's software will upload them to a post

Fryguy

09-05-2006, 10:03 PM

what's impedance of the seas towers? I don't want to look through 37 pages to find it ;)

More specifically, with a bridged behringer a500 (bridges to 8ohm minimum according to manual) drive one?

Dennis Murphy

09-05-2006, 10:35 PM

The tower trends around 4 ohms, with some peaks at the crossover points that are considerably higher, and a dip toward 3 ohms briefly in the midbass. It's basically a 4 ohm speaker, which is what you would expect with the woofers wired in parallel.

Dennis Murphy

09-05-2006, 10:42 PM

They have exactly the same number of components--16.

Edited reply. The Seas will be a little cheaper, however, because I eliminated a 2.0 mH inductor from a shunt circuit. It can also be eliminated from the RS tweeter version with little impact, and I'll probably recommend doing that after a few more simulations.

cobbpa

09-06-2006, 12:47 AM

Alrighty...so basically..a touch cheaper, mostly thanks to the lower cost tweeter. Good deal.

Thank ya Dennis, for the prompt reply & work on these designs!

Rick Craig

09-06-2006, 07:45 AM

what's impedance of the seas towers? I don't want to look through 37 pages to find it ;)

More specifically, with a bridged behringer a500 (bridges to 8ohm minimum according to manual) drive one?

I've designed the tower with the woofers in series. The load averages 6-8 ohms and will be easier to drive. If you have a modest receiver this may be an advantage for you.

Rick Craig

09-06-2006, 07:54 AM

If anyone's interested I can provide some nearfield measurements of the RS225's in an alternative ported box (3" flared port).

cobbpa

09-06-2006, 10:14 AM

jonathanb3478

09-06-2006, 04:36 PM

If anyone's interested I can provide some nearfield measurements of the RS225's in an alternative ported box (3" flared port).

Are the baffle dimensions the same in your alternate box? (42" X 10.75" w/ 3/4" radius roundovers)

What cu ft?

What frequency is the port tuned to?

Dennis Murphy

09-06-2006, 07:44 PM

For an upcoming project in a HT room, these towers may be placed on a shelf 4'-5' up off the floor. In this placement, could the towers be placed upside down? The goal would be to have the tweeter on ear-level as opposed to ~8' high.

Would this create any problems?

It might work acceptably. There may be some lobing issues, but the main difference will be in the bass balance. With the woofers that far above the ground, there will be less bass reinfocement, and effectively less baffle step compensation, so the lower midrange may come out more. This can cause a "hooty" coloration. With this particular speaker, there's a heck of a lot of bass to start with, so it might not be a big deal.

cobbpa

09-06-2006, 08:34 PM

It might work acceptably. There may be some lobing issues, but the main difference will be in the bass balance. With the woofers that far above the ground, there will be less bass reinfocement, and effectively less baffle step compensation, so the lower midrange may come out more. This can cause a "hooty" coloration. With this particular speaker, there's a heck of a lot of bass to start with, so it might not be a big deal.

The less effective bsc would actually be desirable as they would be up against the wall. Cool! :T

Rick Craig

09-07-2006, 08:40 AM

Are the baffle dimensions the same in your alternate box? (42" X 10.75" w/ 3/4" radius roundovers)

What cu ft?

What frequency is the port tuned to?

Are your cabinets the sealed or ported version? If ported, what's the internal volume?

Rick Craig

09-07-2006, 08:43 AM

The less effective bsc would actually be desirable as they would be up against the wall. Cool! :T

If they're going to be against the wall you may want to consider a crossover with the woofers in series. This will give you more control over the power response and amount of BSC you want to add.

GMorris

09-07-2006, 10:36 AM

Rick,

You wrote previously that the woofers in series worked well. Did you have to adjust the crossover for this? Does the sensitivity remain the same?

Greg

jonathanb3478

09-07-2006, 11:30 AM

Are your cabinets the sealed or ported version? If ported, what's the internal volume?

My calculated (based on the design) woofer enclosure volume is 3.06 cu ft. That takes into account all braces, but not the woofers or the crossover. It also does not take into account the damping material. I am hoping that makes it a wash. I selected just over 3 cu ft, mostly because it is when modeling programs showed a ported response that started to be a reasonable option in my opinion.

I actually will be building two different crossover access panels for each speaker. One set will have just the binding posts, the other set will each have the binding posts plus a 4" Precision Port.

I will then conduct a shoot out with no bass management, since these will be used for a stereo only setup in the bedroom. If I like the design, I keep it. If I keep it, I pick sealed or ported. I will then store the other set of access panels, in case I move the speakers to another room or some such.

dynamowhum

09-07-2006, 11:04 PM

Had some delays today. First day off honey do stuff. However; got the cabinet parts trued up and glued the sides and back to the base. Layed out the baffles and made out a punch list for tomorrow. Bought some really neat Jet clamps that have a forked tongue on the end to spread the clamp load I guess.
I did get my cap in from PE as well. Hopefully I will have the box done except for the veneer, tomorrow.
Will not be able to work on it this weekend as I have to go see my folks in Houston. Cheers

Fred

Rick Craig

09-07-2006, 11:15 PM

Rick,

You wrote previously that the woofers in series worked well. Did you have to adjust the crossover for this? Does the sensitivity remain the same?

Greg

The crossover is quite different from what Dennis did mainly due to the series woofers and different acoustic slopes. The sensitivity of my design is 85db and I can drive the speaker quite loud with my 50-watt Denon test amp. If higher sensitivity is needed I would use the unshielded version of the RS150 and run the 225's in parallel since the output levels of the drivers would be better matched.

Rick Craig

09-07-2006, 11:19 PM

My calculated (based on the design) woofer enclosure volume is 3.06 cu ft. That takes into account all braces, but not the woofers or the crossover. It also does not take into account the damping material. I am hoping that makes it a wash. I selected just over 3 cu ft, mostly because it is when modeling programs showed a ported response that started to be a reasonable option in my opinion.

I actually will be building two different crossover access panels for each speaker. One set will have just the binding posts, the other set will each have the binding posts plus a 4" Precision Port.

I will then conduct a shoot out with no bass management, since these will be used for a stereo only setup in the bedroom. If I like the design, I keep it. If I keep it, I pick sealed or ported. I will then store the other set of access panels, in case I move the speakers to another room or some such.

My cabinet is the same volume. What Fb do you plan to use for the tuning? I have a 3" flared port which may be better for your cabinet volume due to the low tuning I used.

jonathanb3478

09-08-2006, 12:27 AM

My cabinet is the same volume. What Fb do you plan to use for the tuning? I have a 3" flared port which may be better for your cabinet volume due to the low tuning I used.

My target tuning is 27.3 - 29Hz. At some point, I will need to make a decision on that. Regardless, however, I believe the max length for that in my box is just under 12". The Precision Port is an inch longer than the calculated length, obviously. I only have an internal depth of 19", so I could not go much lower than that before I have issues fitting the port in the enclosure. I do not think I would want to, anyway. That is based on WINISD simulations of the response of a pair of these in a 86.66L enclosure.

EDIT: I just measured the "diameter" of my cat's head. It is just under 3". If I use a 4" port, I might have to get my cat out of a speaker at some point. :E Maybe a 3" port is a better idea.

Or at least a "port grille" of some kind. :M

dynamowhum

09-08-2006, 08:40 PM

Well just finished glueing it all up but the top lid. I had done some minor projects in the past using MDF, but man I made a pile of dust today putting holes in the baffles. I think I'll do BB plywood next time if I end up doing the mains. I hate working with a dusk mask all day in the heat. I don't have a shop or a garage.
Like anything else I try for the first time it takes twice as long as I thought it would. I mock up everthing and check for fit and square before I glue it up. Kinda of slow but not very many redoes that way.
One more thing. This thing is huge. I gotta get a picture of this compare to my old infinity center channel. LOL. Cheers.

BobEllis

09-08-2006, 09:29 PM

Trust me, you WILL be making the mains so they can keep up with the center. ;)

dynamowhum

09-08-2006, 11:18 PM

Bob I suspect you are correct. LOL.

jonathanb3478

09-09-2006, 02:30 AM

Well just finished glueing it all up but the top lid. I had done some minor projects in the past using MDF, but man I made a pile of dust today putting holes in the baffles.

With out my dust filter equiped respirator, I would have been hospitalized with in the first week of using MDF and my router. I now have used it with its dust collection accessory connected to my shop vac (got that interface worked out, finally), and it is night and day. Where I would have been swimming in MDF dust before, I now have a handful of dust that escapes the DC.

Maybe you do not have/are not using your DC capiblity. I would highly recommend that you start using it, or get tools with DC ports in the future (my table saw has one as well). I used to spend more time cleaning than working. Now I spend ~30 seconds cleaning. :T

dynamowhum

09-09-2006, 08:30 AM

My dust control is a 1 hp shop vac hooked up to my router. I do use a good mask as well. My other tools I used table saw, jig saw, circular saw and drill don't. My little vac is good at pulling the dust away from the project but it is also good at discharging some dust as well. You are fortunate to have a dedicated shop. I hope to build a garage this next year and set it up for dust control with the actual unit outside of the building. Anyway your project is looking very good Johnaton. I'm kinda of torn this weekend I would have liked to have gotten everything but the veneer on but I have a family obligation to take care of. Cheers

jonathanb3478

09-09-2006, 09:20 AM

My little vac is good at pulling the dust away from the project but it is also good at discharging some dust as well.

I run a dust bag and the canister filter that came with my 12Gallon Craftsman shop vac. I was told a shop vac with out a "fine dust" bag would be next to useless as a DC solution for MDF dust. I wonder if you are finding out that that is true. ;)

You are fortunate to have a dedicated shop.

lol

Well, sorta. I live in an apartment. I have no shop. My grandma and aunt live ~16 miles one way from me. They have a 4 bedroom home with a nice covered porch in their backyard. They are both getting a long in years, and just getting the mail sometimes is more than they can handle comfortably. I help with a few little things, and I can store my tools (including my table saw) in the garage. I can then move what I need to use from the garage to the porch, in order to work. As long as it gets moved back when I am done, of course.

So, I get to pay >$4 in gas to get to and from my "shop". I love my Mustang GT, but a 4.6L V8 does not sip gas, even when operated with a manual transmission. I also get to wheel my table saw from the garage to the porch, and back, every time I need to use it.

I still think I am lucky, however. If all I had was my apartment, I would be SOL. ;x(

Anyway your project is looking very good Johnaton.

Thank you!

I also managed to shake loose a bit of money in the budget, so I should be able to get enough MDF and all the hardware to finish up the enclosures in the next couple weeks. No drivers or crossover components for a while yet, however.

dynamowhum

09-09-2006, 12:27 PM

I was fortunate to have the extra cash to do the center, may have to wait on the veneer because I want something nice. Right now nice is out of the budget. But I can wait for that. Also I probably need to buy enough veneer so it will match the mains that will inevitably will come in the future. I think I will do like you for the mains and build the boxes and wait for the extra cash for the electronics. Who knows maybe PE will have another sale on stuff we need by then. Anyway Cheers.

J Walker

09-09-2006, 01:19 PM

jonathanb3478:

I have used one of these to help extend life of the filter in my old shop vac.

http://www.rockler.com/product.cfm?page=1515

Also I have learned that any length of dust collection piping MUST be grounded. Static builds up when dust is moved along plastic. It CAN cause a dust collection system to explode. (Grain bin explosions are the same thing) I personally use something like this. (If the link works) Also reduces those nasty little shocks. :E

http://www.rockler.com/product.cfm?page=2385&SearchHandle=DADBDCDBDADADDDGDIDFGCDHDEDJDBDECNGCGEDADECNDEDBDIDGCNDIDEGFDICNGBGDGCDADJGFDBGBDFGDDDDGDADADADBDCDADADADFHIGEHFHDHEDADADCDGDADADCDCDADADBDIEEEDEDEEEEEFEEEFEEEDEDEEEEEGEEECEEEKDADADADBDFDADADADBDADADADADADADADADADADADADBDADADADADFHIGEHFHDHEDADADADBDB&filter=xdust

Hope this helps.

Jimmy Walker
Pearl, MS

ThomasW

09-09-2006, 09:32 PM

PEOPLE, PLEASE, LETS STAY ON TOPIC

It's hard enough to get people interested in reading this huge thread without all the tangental OT chats cluttering it up.....

Dust collection is a great topic for a separate thread in the main DIY forum.... :T

ssabripo

09-09-2006, 09:45 PM

waiting for Chuck to chime in here with the pics, but I'll go ahead anyways:

I took my CC (CurtC XO) to compare it to CHuck's CC (Dennis XO). THere was no REQ, no Mic, no scientific data....just plain ol' ears! :B

anyhoo, in a nutshell: they are EXTREMELY close!! :E The low end and the highs were pretty much identical, and so was most of the mids. The only area that you could tell a slight difference is right around where the woofers and the mid crossover (I think it is about 300hz +-50hz)....and even then, the difference was small (dunno which one was "better" to be honest).

I could elaborate more, but I will wait for chuck to give his 0.02..... but my conclusion is: they are practically the same "sound"; the acoustical signature was incredibly close :T

jonathanb3478

09-10-2006, 11:32 AM

I took my CC (CurtC XO) to compare it to CHuck's CC (Dennis XO). THere was no REQ, no Mic, no scientific data....just plain ol' ears! :B

Hopefully Chuck shows up soon to add his $.02, but I could have swarn that Dennis was not quite done with his XO, yet. The one Chuck was making was for further testing/refinement, correct?

Just wondering.

chasw98

09-10-2006, 10:35 PM

OK, here you go...... I guess you could call this "DIY Heaven" or "Murphy's Place" From left to right, you will see, DIY subwoofer, DIY WWMT DM XO w/SEAS, DIY BlackFlame Ambient Light Screen, DIY WMTW DM XO w/RS28, DIY WMTW CurtC XO, DIY WWMT DM XO w/Seas.

http://i21.photobucket.com/albums/b297/chasw98/DSCN3866.jpg

As far as an opinion on the difference between the WMTW's, it is very hard to say because of the way it was listened to. sab brought his in and threw it on the couch. We listened to mine in 7 channel stereo with the L&R disconnected and the surround power amp shut down so it was center only and the sub turned off with all the speakers set to large. After 5 minutes we put his in place of mine and listened for another 5 minutes, then we went window shopping. There is a difference and I felt it was in the mid bass region where the woofs crossed over to the mid, but I really can't say. And they both sounded superb. Stay tuned, I am building some A/B devices, got my mic back from KimG calibrated and am preparing my outdoor testing rig.

Jonathon - The center WMTW I am running is the RS28 model as per DM, I have a Seas just waiting to go in with an assortment of components when DM posts his schematic or if he sends it to me to build for him to test it.

Chuck

Dennis H

09-11-2006, 01:42 AM

So, Chuck, how do you watch a movie with all those speakers blocking the screen? ;)

jonathanb3478

09-11-2006, 04:31 AM

Jonathon - The center WMTW I am running is the RS28 model as per DM, I have a Seas just waiting to go in with an assortment of components when DM posts his schematic or if he sends it to me to build for him to test it.

Ahh, I see. I was assuming things were further along than they are. You would think I would know better. :oops:

As of right this minute, both of my enclosures are in the same build state as the pics in my construction thread. I am waiting on a cable order to arrive in the middle of next week. At that point I will have the batting in the other enclosure, and once I have wired them up for the drivers, I will glue on the internal side panels. I should have my next sheet of 3/4" MDF by then, and I can start cutting the external enclosure pieces.

Slow but steady wins the race, right? :T

chasw98

09-11-2006, 05:21 AM

So, Chuck, how do you watch a movie with all those speakers blocking the screen? ;)

The screen is being moved up and to the right shortly (next couple of weekends when my son is available for help). I also need to redo the rack and fit the componenets inside, but all in time.

Dennis Murphy

09-11-2006, 09:42 AM

Heeeeyyyyy Chuckster I sent you the schematic last week. Did it get lost in the ether?

chasw98

09-11-2006, 10:34 AM

Heeeeyyyyy Chuckster I sent you the schematic last week. Did it get lost in the ether?
I believe so, I have received nothing. I will PM you with details.

Chuck

Dennis Murphy

09-11-2006, 07:27 PM

I checked my sent folder--you should have got the schematics a week ago. I sent them again.

chasw98

09-11-2006, 08:21 PM

Just got your latest email with the schematics and replied twice with info.

And so everyone knows....... I should have the WMTW Seas H1212 XO off to Dennis on Monday afternoon.

That keeps me honest so I don't let you guys down!

jonathanb3478

09-11-2006, 08:30 PM

And so everyone knows....... I should have the WMTW Seas H1212 XO off to Dennis on Monday afternoon.

So what are we going to do to him if he misses this deadline?

I have some ideas... :evil: :evil: :evil:

:E

:B

Dennis Murphy

09-11-2006, 08:36 PM

[QUOTE=chasw98]Just got your latest email with the schematics and replied twice with info.

Hmmm I got one reply, but with no info. The information highway seems to have a few detours.

chasw98

09-11-2006, 10:26 PM

[QUOTE=chasw98]Just got your latest email with the schematics and replied twice with info.

Hmmm I got one reply, but with no info. The information highway seems to have a few detours.
I replied the 1st time with
"Just got it!"

I replied the 2nd time with
"Dennis:
I have all the parts EXCEPT the 1.5mH inductor. I got a 15 gauge air core and it will be here by Friday. I will rebuild my XO to match your schematic (and probably take a quick listen), then send it to you Monday by UPS from work.
Chuck "

And I just replied the 3rd time with
"Would the tweeter level be set by changing the value of the 12 ohm resistor that is in parallel with it?"

Hope you got all 3. There were no attachments.

cobbpa

09-13-2006, 12:20 AM

Would an amp like the value Nady amps be reccomendable to power these? Or would a source like that just sound bad through them? I haven't seen a whole lot of opinion on what they're being driven with & all, just that you can 'hear your equipment'.

Exocer

09-14-2006, 08:46 PM

This question has probably already been answered. But how would the WMTW center mesh with Natalie P mains?

Edge540

09-17-2006, 01:14 PM

I thought i would post a picture of the three speakers i built. The center obviously still needs the baffle painted but i couldnt wait to hear all three of these together playing SACD/DVD-A. Only one word describes this set up...WOW. If there is anyone sitting on the fence deciding to build these or not, DO IT! You will not regret!
Thank you goes to the guys that did the design work on these.
The next project, is the 320L Sonosub.
What comes next...I have yet to decide.
Thanks Again,
Eric

jonathanb3478

09-17-2006, 02:03 PM

I thought i would post a picture of the three speakers i built.

I can't speak for anyone else, but I would like to see more pics, including some close-ups. In the image you provided, they really look very nice. Unfortunately though, it is hard to see things like baffle roundovers, floor spikes, and the gloss level of the finish used on the baffles.

Post um!!! :T

dynamowhum

09-17-2006, 08:15 PM

Okay well tomorrow I am going to be putting my sound padding in my center. Do I just do the walls and not the floor and lid of the box? I got the egg crate like stuff from PE. Thanks.

Edge540

09-17-2006, 09:36 PM

Here are three more photos. The baffle is gloss black and i see now that it shows fingerprints quite nicely on photos. If there is something specific youd like, just let me know
eric

jonathanb3478

09-18-2006, 03:51 AM

Hey, Chuck!

It is Monday.

I just had an overwhelming urge to mention that, randomly. :B

jonathanb3478

09-18-2006, 03:58 AM

Here are three more photos. The baffle is gloss black and i see now that it shows fingerprints quite nicely on photos. If there is something specific youd like, just let me know
eric

I like the way you did that base for each speaker. It seems that those bolts hold it on. Very nice!

chasw98

09-18-2006, 07:49 AM

I have sent off the rebuilt crossover using the Seas H1212 tweeter! I have also attached a picture for those that wish to save it and zoom in on it.

Chuck

Dennis Murphy

09-18-2006, 09:16 AM

chasw98

09-18-2006, 10:01 AM

Hmmmm. There aren't any random wires sticking out or loose components dangling over the end. I'm not sure I'll know how to use it. But thanks for doing the dirty work! It's looks great. I'll give it a good listen and see if it's soup yet.

Oh, it's soup alright! But I will let the chef take care of the ingredients. ;x(

PS - I was told to build it on a piece of cardboard so you would feel more at home. :rofl:

kgveteran

09-18-2006, 01:46 PM

ssabripo

09-18-2006, 02:04 PM

Another happy customer! This is one hell of a design.

KG
Indeed!! :T

yo KG...did you see the A/B comparo Chasw98 and I did on the DM vs CurtC XO's?? I think you are good to go with the XO's we got...they were sooooooooo close! :W

chasw98

09-18-2006, 02:49 PM

Indeed!! :T

yo KG...did you see the A/B comparo Chasw98 and I did on the DM vs CurtC XO's?? I think you are good to go with the XO's we got...they were sooooooooo close! :W

Well, I guess we will have to do it again when the updated Seas XO comes back. :E :E

ssabripo

09-18-2006, 05:01 PM

you really think the seas + updated XO will sound a whole lot better?! I seriously doubt it, but I could be wrong...what I heard from both of our centers was pretty darn awesome, and I can't imagine a tweeter and new XO making a drastic improvement. Perhaps a slightly smoother high, and slight improvement in blending with the mid on the upper region of the bandpass, but dunno how much real world difference you would see.

now, put a pair of Seas Excel woofers and mid, and new XO, and THEN we talking...:D

hohe2112

09-18-2006, 08:51 PM

Has anyone tried these with the 27TDFC instead of the 27TBFC/G? I'm thinking of doing a complete 7 speaker set and matching the mains and center to one of the MT or MTM projects here in Missions Accomplished for surrounds. All of those projects use the DFC, and generally my tastes lean toward soft dome tweeters. My hearing is super-sensitive to high frequencies, and metal domes tend to sound harsh to me, although I have to admit I've never heard the BFCs. I've read elsewhere in this forum that from a crossover standpoint, the two are interchangeable, so I think I'll be safe using either for all 7 speakers. Either that, or if anyone has listened to these side-by-side and can compare and comment on the sound of each, that would be great, too. ;)

Thanks!
80sMike

Rick Craig

09-18-2006, 10:44 PM

dynamowhum

09-18-2006, 11:06 PM

Box is now all glued up. Installed a sub woofer 4 terminal cup because I am running an outboard cross over box. Before I put the lid on I glued in the egg crate foarm on the side walls. One last thing I put the box on the digital bathroom scales and it weighed in at 52 lbs. Thats sans speakers and XOs. Will weigh it again when complete.
I plan on mounting the speakers tommorow and start soldering the XOs. Cheers

ifeliciano

09-18-2006, 11:12 PM

I have sent off the rebuilt crossover using the Seas H1212 tweeter! I have also attached a picture for those that wish to save it and zoom in on it.

Chuck

Hi Chuck,

Treat me like im stupid here, but tread litely :B :evil: I understand the issues when mounting inductors too close to each other, but is it necessary to keep the resistors so far apart ? Is it possible to layout this XO in a smaller perf-board ?

dynamowhum

09-19-2006, 09:05 PM

Well gang got my box complete today and sitting on top of my rack in its temporary location until I get my projector. Tomorrow I should get the XOs done and tested to see if they work. On a side note got my IB re installed and like the look a lot more. Cheers.

Inu_Yasha

09-20-2006, 05:59 AM

Please post some pics! I really enjoy looking at the pictures of people's work. Right now I'm saving up enough money to do the RS Center and the Modula MT's over christmas break, so any pictures of crossovers or boxes will help :)

chasw98

09-20-2006, 06:03 AM

Hi Chuck,

Treat me like im stupid here, but tread litely :B :evil: I understand the issues when mounting inductors too close to each other, but is it necessary to keep the resistors so far apart ? Is it possible to layout this XO in a smaller perf-board ?

Out of all 3 components resistors, capacitors, and inductors, the inductors are the only ones where physical placement is to be considered. You can cram resistors and capacitors as tight as you want. I just had the real estate to use in this project. If you look at ssabripo's center he did it on 2 very small circuit boards.

Chuck

ssabripo

09-20-2006, 09:11 AM

Out of all 3 components resistors, capacitors, and inductors, the inductors are the only ones where physical placement is to be considered. You can cram resistors and capacitors as tight as you want. I just had the real estate to use in this project. If you look at ssabripo's center he did it on 2 very small circuit boards.

Chuck
agreed.

feliciano, I would still encourage you to get them all in a single board like Chuck did, and most importantly, mount the plate onto a back openinig for simple access like Chuck. Mine is a smaller circuit board, but they are all inside in three different parts of the CC, and frankly, it is nearly impossible to access should something go wrong :oops:

http://www.htguide.com/forum/showpost.php4?p=251432&postcount=468
http://www.htguide.com/forum/showpost.php4?p=251665&postcount=482

dynamowhum

09-20-2006, 11:56 AM

Inu Yasha I would love to post some pics but right now I have no camera. I will buy one soon as I can but right now all my extra mad money is going into the speakers. Sorry.
That inaccessablity to the XOs and it being my first build is what kept me from putting mine inside the center channel. I know me to well. Please don't get it confused when I say I know murphy real well that it doesn't have anything to do with the Dennis on this board. LOL. Cheers.

dynamowhum

09-20-2006, 12:01 PM

Case in point about being aquanted with Murphy, Murphys Law that is. The other day I weighed my center box and it came in at 52 lbs. Last night I put my speakers in the box and tried to weigh them and my digital bathroom scales went crazy. I guess the magnets in the speakers screwed up my scales. Wifey is a little ticked at weighing 1000lbs right now.

Brian Walter

09-20-2006, 12:52 PM

Wifey is a little ticked at weighing 1000lbs right now.

Try weighing the speaker again, maybe you'll screw it up so that she will only weigh 98 lbs, she'd be really happy then, assuming she weighs more than that for real.

ifeliciano

09-20-2006, 01:44 PM

BigJim_inFLA

09-20-2006, 02:12 PM

dynamowhum

09-20-2006, 02:57 PM

Well Bryan lets just say she would be considerably happier if that was the truth! But well killing the digital scale had a silver lining. Went to Wally world with the wife to get new scale and talked her into getting a new digital camera. It's a cheapy $80 for 6.1 megapixels. But hopefully it will be good enough to post some pics. Way cool.
Thanks for posting BigJim. I went with a different enterior baffle set up. I put a baffle that runs parallel with the front and behind the mid/tweet section with 7" holes directly behind the woofers. Then behind the mid/tween section I ran 2 baffles running perdendicular to the front baffle with 2 sets of 2" holes in each. Hope my description is clear.
I really have the urge to build the WWMT ala Brian/Mike versions. I wonder what it would look like if the back setion went to more of a point. I was envisioning something that looked like a tear went you look down from the top. I would/could call them my tears, corny aint it. Cheers.

Inu_Yasha

09-20-2006, 09:48 PM

What material did you mount your crossovers on? Also, might I ask how much the total bill was for the center?

dynamowhum

09-20-2006, 10:27 PM

I used precut 8X10" clear lexan sheets from Lowes. As Thomas W pointed out it does scratch so it is best to leave the cover sheets on each side till you have it all done then peel them off. I do think Chas 98 pc boards are sturdier.
As far as the total cost goes were do you stop? My bill from PE was $500 but that included a $35 book and $50 dollar SPL meter. Then I bought about $80 in supplies from Radio shack, $30 of that was for a soldering gun. At lowes bought a $20 up cut spiral bit, had the other two needed, add $10 in tite bond III glue and $60 in extra clamps. Oh yeah forgot about $32 for the MDF. Probably $30 or so on stuff I forgot. I have not veneered this thing yet. Got no idea what that will run yet it could be $100 to $400 for that. Then I got to get test equipment, $50 mic, $10 cable, maybe an M-audio pre usb ala Thomas W $150.
Anyway for a begginner in all this it is certainly more than the price of the BOM. I have a lot of wood working tools. YMMV. Now all this being said once you get all the tools and test stuff then yes it is a matter of BOM + box + disposable supplies. Cheers.

BigJim_inFLA

09-20-2006, 10:49 PM

What material did you mount your crossovers on? Also, might I ask how much the total bill was for the center?

1/8" clear acrylic sheet. I like it because I can score it with a knife and snap it. I live in an apartment and do most work by hand so the less sawing the better. I think the total is somewhere around $300.00 not including the veneer and paint. I bought all my drivers for LCR at once to get the quantity discount.

chasw98

09-21-2006, 09:01 PM

OK, boys, read em and weep! Dennis has just gotten the initial plot of the Seas tweeter for the WMTW center channel. Looks mighty fine to me!

http://i21.photobucket.com/albums/b297/chasw98/center%20channel/seasxo092106.gif

he will have more listening impressions later on.
Chuck

Jim Holtz

09-21-2006, 09:06 PM

OK, boys, read em and weep! Dennis has just gotten the initial plot of the Seas tweeter for the WMTW center channel. Looks mighty fine to me!

he will have more listening impressions later on.
Chuck

That is a perfect match for the mains. :T Awesome!

Jim

dynamowhum

09-21-2006, 10:19 PM

Very nice indeed. Congratulations.

Brian Walter

09-21-2006, 11:13 PM

Jim Holtz

09-22-2006, 06:15 AM

That's great, I just whish he had designed the center with the RS180 instead of the RS225. The box is just a little too big for me. But maybe I can put it under my TV instead. I suspect that would probably require a crossover tweak as the effective baffle would probably be enough different to affect the frequency response. Oh well, I can only hope or try my own design.

Brian

Hi Brian,

Here's what you are looking for:

http://www.selahaudio.com/id115.html

It'll match your mains perfectly and have great off axis dispersion. It could easily be built ported in a one cube cabinet with extension to the 30's same as the Natalie P's.

Jim

Brian Walter

09-22-2006, 08:50 AM

Jim Holtz

09-22-2006, 11:30 AM

Hi Jim, I've looked at that design quite a bit and may end up with it in the end. It does look like a really nice design. The biggest potential problem with that design is that the MDM55 is not very well shielded and the tweeter isn't at all, so it will likely interfere with my TV. The wife has already said no to a new TV, so that's not an option. I've also talked to Rick about revising the design to use a shielded tweeter, I'm just not sure which one I'd like to use, any suggestions? I wonder if I could use the 27TDFC-TV and replace the diaphragm with the one from the 27TBFC? Then I'd have the same basic tweeter across the front channels.

Brian

Hi Brian,

The only place that I know of that carries the shielded version of the 27TBFC/G is Solen. It is the 27TBC/GTV06 (no ferrofluid in this version) and sells for $37 USD. I emailed Josh at Madisound about the possibility of using the 27TBFC/G voice coil replacement on the shielded 27TDFC and he said it wouldn't work with that tweeter for some reason. The one from Solen is certainly an option and would match the mains perfectly.

The MDM-55 isn't totally shielded, but with the neo magnet, I wouldn't think there would be a problem. Rick should be able to tell you how close the MDM-55 can be without causing an issue.

Rick also has a Daytek center design with RS180's, MDM-55 and Fountek NeoCD3 ribbon which should be ultra low interference with the TV. It's in the Gallery and looks like a super nice center design. I have no problem integrating my center with a Hiquphon OWIII and the Fountek JP2 ribbons so I doubt that it'd be an issue with the 27TBFC/G either. That said, I don't listen to SACD or DVD-A in surround so my center channel is only used for movies and the occasional music video.

Jim

Dennis Murphy

09-22-2006, 12:12 PM

he will have more listening impressions later on.
Chuck

I took the day off to finish up a whole lotta projects this weekend. I spent the morning with the Seas center channel. This one is a wrap. I changed a couple of resistor values slightly, but nothing that changes the basic character, and one of the changes is optional--it cools down the tweeter slightly. I find the flat setting a bit much at high volume. One word of caution to anyone thinking of building the mains or center channel. These are "up front" speakers. My primary objective was to provide as clean and transparent a midrange as possible. I've found that this is usually best accomplished with 2nd order acoustic slopes when the drivers are capable of it. The result best replicates what I hear when I'm sitting in front of a real orchestra. But these are not laid back designs. If you plop them down in a room with hardwood floors, drywall, and not much else, things could get a little, uh, exciting. You can offset this to a point by adjusting the tweeter L-pad. But if you go too far, you will compromise the phase coherence around the crossover region and lose the "see-through" quality. I'll specify one alternative setting when I send the final schematic to Chuck, who I thank very much for assembling the crossover. He did a great job, and has already agreed to spend the rest of his life building crossovers for me for free.

cobbpa

09-22-2006, 12:18 PM

Good to hear, especially with the "up front" quality, since in my application they will be near a wall...may end up sounding good to us! Good work!

Brian Walter

09-22-2006, 12:20 PM

dynamowhum

09-22-2006, 12:30 PM

Dennis I have built but not yet tested your RS based center sealed version. It will be placed behind an acoutically transparent screen in a few months. Is there anything I need to do to the crossover for this situation. Thanks in advance.

chasw98

09-22-2006, 12:33 PM

and has already agreed to spend the rest of his life building crossovers for me for free.

I don't have a problem doing that. I am positive the fringe benefits are worth it. :T

Jim Holtz

09-22-2006, 12:42 PM

Jim,
Thanks for all the information, I didn't know that Solen carried the shielded version of the 27TBFC/G, nor did I know anything about Rick's Daytek CC. When I talked to Rick about the MDM55 he thougth it might interfere if it were placed right on top of the TV, but if I was to set the CC upside down with the MDM55 on top, he thought it would be fine. But then I would certainly need a shielded tweeter. I'm beginning to like the idea of the Daytek design.

Brian Walter

Brian,

If I were to replace my center, the Daytek would be my 1st choice since I have ribbons in my linarrays. I really like the W-M/T-W RS 3-way that Dennis just signed off on too but you've got to have the room for one. It is large but should have great sound quality if it comes close to the RS 3-way mains.

Jim

Jim Holtz

09-22-2006, 12:51 PM

One word of caution to anyone thinking of building the mains or center channel. These are "up front" speakers.

Dennis,

Another great job, as usual of course. :T

I did want to comment on the sound being forward. I certainly wouldn't call the RS 3-ways recessed but I also wouldn't necessarily call them forward either. My impression is that they image with the performers between the front plane of the speakers as you would expect.

How about hopping on a plane and flying out to Iowa for the DIY event on October 28th so you can hear at least a couple different pairs of your creations in person? :D We'd love to have you attend again. I'm co-hosting this time so I'm going to have a lot more "play time" during the event this year.

Jim

Dennis Murphy

09-22-2006, 02:43 PM

Hi I'm afraid I can only take one trip West--and that will by the RMAF in October. I need to hear other designs now and then. I didn't really mean the sound is "forward" in any kind of exaggerated sense. There just isn't anything resembling a BBC dip that seems to be popular in a lot of designs. That U-shaped response can be relaxed and pleasing, but when the heavy stuff comes on stage, you realize something is missing.

Dennis Murphy

09-22-2006, 02:44 PM

beto

09-22-2006, 03:01 PM

[QUOTE=Dennis Murphy]Hi I'm afraid I can only take one trip West--and that will by the RMAF in October. I need to hear other designs now and then.

Dennis are you going to be in the RMAF all 3 days? it would be a pleasure to me et you and everyone else on this board.... hope to run into all of you here..

chasw98

09-22-2006, 03:12 PM

I live 5 minutes from the venue.

Party at Thomas' house!!! :rofl: ;b> :party: :banana:

technimac

09-22-2006, 03:13 PM

ThomasW

09-22-2006, 03:18 PM

Party at Thomas' house!!! :rofl: ;b> :party: :banana:For the past 2 yrs people have come over Sat or Sun in the late afternoon for a 'meet and greet'. Most don't have the opportunity to ever hear 1 IB sub, let alone 2 in one location.... :T

If I'm in a good mood I fire up the big planars (http://pwp.t-3.cc/ttriff/page151.jpg) and give people a listen to those as well... :B

So this thread doesn't get all clogged up I'll start a thread about this in the main section of the forum

beto

09-22-2006, 03:56 PM

For the past 2 yrs people have come over Sat or Sun in the late afternoon for a 'meet and greet'. Most don't have the opportunity to ever hear 1 IB sub, let alone 2 in one location.... :T

If I'm in a good mood I fire up the big planars (http://pwp.t-3.cc/ttriff/page151.jpg) and give people a listen to those as well... :B

So this thread doesn't get all clogged up I'll start a thread about this in the main section of the forum

You live 5 mins from the venue? Great me too! Would love to stop by your place to hear your setup, that is, if you are planning on having a meet and greet..

Eventhoug I recently found this thread, I have read all of it and I am building the DM CC, which I need to finish the XO.

Jim Holtz

09-22-2006, 04:20 PM

Jim,
"The only place that I know of that carries the shielded version of the 27TBFC/G is Solen. It is the 27TBC/GTV06 (no ferrofluid in this version) and sells for $37 USD."

After reading your post, I had a brief moment of hope that the 1213 was available here, but unfortunately that's not the case.

I checked Solen's Seas stocklist and they don't carry the (1213)TBFC/GTV, which is the matching ferro-fluid damped shielded version of the 27TDFC/G.

The (1148) 27TBC/GTV06, that you refer to, the "non-ferrofluid" version of this series, is not as close to the 1212 as the 1213 is.

There are signicant differences between the 1213 and 1148, in terms of fs (750 vs 900Hz) and power handling (220 vs 150W), that may be problematic when attempting to use it in a system with the 1212's.

OTOH it might be worth trying the 1148 in cases where shielding is essential.

It would be very nice if either Solen or Madisound ordered in some 1213's, now that the 1212's have earned such a high reputation for their performance.

Cheers, Bruce

Hi Bruce,

Actually, Brian was asking about recommendations for a custom design from Selah Audio that he's considering. Although, I suspect that even with the different specs the 1148 would probably work fine in the center if someone wanted a 100% shielded RS 3-way center.

I've discussed the H1213 with Josh at Madisound and he said that they wouldn't be carying it. Shielded tweeters are extremely slowe moving items for them as I understand from our conversation.

Jim

JonP

09-22-2006, 04:32 PM

As far as the total cost goes were do you stop? My bill from PE was $500 but that included a $35 book and $50 dollar SPL meter. Then I bought about $80 in supplies from Radio shack, $30 of that was for a soldering gun. At lowes bought a $20 up cut spiral bit, had the other two needed, add $10 in tite bond III glue and $60 in extra clamps. Oh yeah forgot about $32 for the MDF. Probably $30 or so on stuff I forgot. I have not veneered this thing yet. Got no idea what that will run yet it could be $100 to $400 for that. Then I got to get test equipment, $50 mic, $10 cable, maybe an M-audio pre usb ala Thomas W $150.
Anyway for a begginner in all this it is certainly more than the price of the BOM.

Hehehehe... Somwhere, out there, there's a website documenting someone's first build. And he's got my kind of sense of humor, with a very quotable quote of the whole DIY process: (paraphrasing)

"What!! Save hundreds of dollars building your own high quality speakers by buying thousands of dollars of woodworking tools??? I'm IN!!!" :T

Jon

PS... Zappa rules!!

Dennis Murphy

09-22-2006, 05:58 PM

[
Dennis are you going to be in the RMAF all 3 days? it would be a pleasure to me et you and everyone else on this board.... hope to run into all of you here..[/QUOTE]

I'll be there from Friday noon until Saturday night. I have to leave bright and early Sunday to make it back for a concert at 3:30. Bummer. Hope we can hook up. I'll be hanging out at the SalkSound-Van Alstine room quite a bit. Frank V.A. selected the HT3's to demo his amps, and I sure want to meet him and see how it all sounds.

beto

09-25-2006, 04:28 PM

I have sent off the rebuilt crossover using the Seas H1212 tweeter! I have also attached a picture for those that wish to save it and zoom in on it.

Chuck

If I understand it right, and in comparison with the DM CC XO with the RS28,
on his new XO for the Seas H1212:

1. the low end section is the same.
2. the mid section is different as there is no L2 right?
3. the hi section, of course, is all new.

I have drawned my own circuit based on what I see on your picture, I know I have the low and hi end right, but the mid, I am wondering, but its possible I have it right too?

chasw98

09-25-2006, 04:42 PM

If I understand it right, and in comparison with the DM CC XO with the RS28,
on his new XO for the Seas H1212:

1. the low end section is the same.
2. the mid section is different as there is no L2 right?
3. the hi section, of course, is all new.

I have drawned my own circuit based on what I see on your picture, I know I have the low and hi end right, but the mid, I am wondering, but its possible I have it right too?
1) - Correct
2) - Sort of
3) - Not all new

So far, I built the prototype and sent it to Dennis. He is the only one that knows the final components right now.

dynamowhum

09-26-2006, 04:33 PM

It is up and running. : :D I would like to thank everybody that contributed to this design and helped me with my questions. :T Thanks ever so much. In a week or so I should be testing this bad boy once I get all the testing stuff in. Cheers.

cobbpa

09-29-2006, 03:12 PM

chasw98

09-29-2006, 06:47 PM

Hey chuck, or dennis...concerning the Seas center xover pic
Is the 3.2 uf cap the only one in the tweeter circuit?
What components make up the mid's low pass section?
What resistor values are good to combine for 17, 12, and 40 ohms, using the available Mills values (http://www.partsexpress.com/webpage.cfm?&DID=7&WebPage_ID=110)?

We're making a big purchase at the PE sale tomorrow..hopefully I can get a response by morning :) Thanks!

The circuit for the DM Seas XO has not been finalized by Dennis yet, but I can give you the values I used in the prototype which are very close to the final, I believe.

High
01) 8.2 Mf
02) 8 ohm
03) 1.2 mh
04) 3 ohm
05) 12 ohm

Mid
01) 57 mf
02) 40 ohm
03) 1 ohm
04) 17 ohm
05) 1.5 mh
06) 1 ohm
07) 3.3 mf
08) .1 mh

Low
01) 4.7 mh
02) 100 mf
03) .55 mh

If you bought a selection of 1, 3, and 4 ohm resistors, you should be able to make up any combo of 1, 8, 12, or 17 and have the ability to change them when the final schematic comes out. Good luck!

m1ke323

10-01-2006, 11:30 AM

I finally finished my crossovers on friday. I installed one crossover and had to go listen to the first speaker. I hooked it up to my Rotel-1080 and listened to it for about a half hour. It absolutely killed my old Klipsch speakers. That is until the RS28 tweeter blew. I have a Denon-2807 receiver and I only brought the volume up to reference (0db on the receiver). Most of the time I was listening to the volume at about -20db to -10db but I just wanted to see what it could do at 0db like I sometimes listen to my movies at. The volume goes way past zero up to like +15db. Anyways my point is, the tweeter blew when it shouldn't have. Anyone have any idea why this is?

Also, is there any power regulator I can solder into my tweeter crossover so this doesn't happen?

The only bad spot on my crossovers I could find is where I connect all the positives from the high/mid/low XO's into 1 so I can hook it up to the terminal plate. The same goes for connecting all the negatives at the terminal plate. I am using Apex's 11 guage wire and haven't found a good way to connect 3 wires together. My joint is just twister and soldered. Anyways I though maybe more power is going to the tweeter becuase of a bad solder or something. But the speaker sounded find, all the speakers were getting power so that may be a dumb idea. Anyways, please help.

Thanks
Mike

jonathanb3478

10-01-2006, 01:57 PM

That is until the RS28 tweeter blew. I have a Denon-2807 receiver and I only brought the volume up to reference (0db on the receiver). Most of the time I was listening to the volume at about -20db to -10db but I just wanted to see what it could do at 0db like I sometimes listen to my movies at. The volume goes way past zero up to like +15db.

Well, I would say that by the time you brought the preamp section of the Denon to 0dB, the amp section of the Denon was being asked to put out a bit more power than it is capable of, cleanly.

Receivers need to be able to have the volume knob give high volume with a variety of sources. Some of the source components that might be connected to it, could output at a very low level and require the gain to be turned way up (like +13dB, say) in order to play loud enough.

The thing is, the vast majority of items you will ever connect to your receiver output much higher levels than this "worst case" hypothetical low level output component. That means, for all practical purposes, much of the gain your preamp section can bring to the party is extreme overkill. It will cause a condition where your amp is asked to output an amount of wattage it cannot reach with out a good amount of distortion.

This distortion is mostly spurious high frequency energy. This extra HF to the tweeter causes excessive heating of the tweeter's voice coil, until the adhesive holding it to the driver fails.

Just my guess, but I would say this is what happened to your tweeter.

m1ke323

10-01-2006, 02:07 PM

Thanks John, but I would think that the Rotel 1080 should be able to drive the speakers without breaking a sweat. The Rotel-1080 is rated at 200wpc at 8ohms and 340wpc at 4ohms.

If the Rotel is driving them cleanly it shouldn't produce the extra HF thus not overheating the driver? I won't pretend to fully understand this part, just my guess?

I have some crapping little klipsh bookshelf speakers I have been using for a few years and I can turn those as loud as I want and never worry about blowing them with the same equipment. Those are 8ohms though, but still they are time bookshelves.

chasw98

10-01-2006, 02:23 PM

I hooked it up to my Rotel-1080 and listened to it for about a half hour. It absolutely killed my old Klipsch speakers. That is until the RS28 tweeter blew. I have a Denon-2807 receiver and I only brought the volume up to reference (0db on the receiver).

Mike, from what you said above, it appears you are using the Denon 2807 as the preamp and the Rotel for the power amp, at least for left & right main. Have you ever used a sound level meter to see what O (zero) on the Denon equates too in terms of SPL? When you turn up a preamp and it sends out a very large signal that makes a power amp clip, you are essentially sending a square wave to the drivers. The most sensitive driver and the first to blow will be the tweeter. I am using Earthquake amplifiers rated at 600 watts/ch into 4 ohms and I have not had any problems. I do have clip lights and I can barely get them to flash when I play the beginning of Revenge of the Sith at extremely high volumes. Otherwise, I have plenty of headroom for peaks.

As far as protection for the tweeter, you can put a fuse in line with it. It is very easy to calculate the value needed and then use a slo blo fuse so it does not blow every time there is a large peak. OTOH, with that Denon and Rotel combo, I believe if you were to calibrate it, you wouldn't have any problems in the future.

Chuck

m1ke323

10-01-2006, 02:36 PM

You are correct Chuck, the Denon 2807 is the pre and the Rotel-1080 is the power amp. Do you really think the Rotel could be clipping? I would have thought that 340watts at 4ohms would have been more then enough to power them and not clip. But I am willing to sell it and upgrade if that is what is what it will take to keep from clipping.

I do not have a soundlevel meter to check the SPL unfortunately.

The general concensus seems to be that my amp is clipping, is it possible I was just feeding it to much power?

Mike

ThomasW

10-01-2006, 03:47 PM

The general concensus seems to be that my amp is clipping, is it possible I was just feeding it to much power? Not clipping, just too much power to compensate for a tweeter wired out of phase. And running a single speaker at an out level normally used for several speakers

http://www.htguide.com/forum/showthread.php4?t=22510

BTW spend the $40 and buy an SPL meter...

dynamowhum

10-01-2006, 04:08 PM

Mike to make your wiring problem a little easier you might go with dual terminals. This would give you more terminals to attach your wire to. Cheers.

Dennis Murphy

10-02-2006, 11:16 AM

[QUOTE=ThomasW]Not clipping, just too much power to compensate for a tweeter wired out of phase. And running a single speaker at an out level normally used for several speakers...........

I'm getting a little cornfused. Which crossover is this? And why would the tweeter be wired out of phase? And why would that matter as far as power handling is concerned?

soho54

10-02-2006, 11:54 AM

And why would the tweeter be wired out of phase? The RS150 was wired incorrectly.

And why would that matter as far as power handling is concerned?ThomasW - "It would be out of phase. So it won't sound as loud as if it were in phase. That might have caused you to turn it up the volume to compensate."

ThomasW

10-02-2006, 12:02 PM

Dennis,

Sorry for the 'cornfusion'..... ;)

That was a typo on my part, Mike posted this....
Well I found out that I never reversed my connection on my RS150 like the plan calls for. I connected all the speaker positive to the positive wires and the same for negatives. I typed out of phase 'tweeter' instead of out of phase 'driver'

At the time I was a bit distracted as I was trying to follow both threads here about blowing the tweeter, and I was simultaneously moderating someone acting like a fool on the IB subwoofer forum.

Dennis H

10-02-2006, 12:02 PM

jonathanb3478

10-02-2006, 09:19 PM

nulls cancelling much of the sound
340 watt amp
inefficient former speakers
only one new speaker playing
turned it up to former knob position even though it was "much louder" than several of the former speakers
BOOM -- pilot error

<- +1

Fryguy

10-02-2006, 10:26 PM

What size female disconnects are required for each of these speakers?

Dennis Murphy

10-02-2006, 11:53 PM

Sounds like it's your crossover because in the other thread he says "Well I found out that I never reversed my connection on my RS150 like the plan calls for. I connected all the speaker positive to the positive wires and the same for negatives." So he would have had big nulls near 300 and 2500 and simply turned it up too loud.

nulls cancelling much of the sound
340 watt amp
inefficient former speakers
only one new speaker playing
turned it up to former knob position even though it was "much louder" than several of the former speakers
BOOM -- pilot error

I guess. Except that his initial reaction to the speaker was positive. And I can assure you that these things will sound like crap if the midrange isn't reversed. That assumes, of course, that everything else was wired correctly. So I'm still a little cornfused.

ThomasW

10-03-2006, 12:33 AM

I guess. Except that his initial reaction to the speaker was positive. And I can assure you that these things will sound like crap if the midrange isn't reversed. That assumes, of course, that everything else was wired correctly. So I'm still a little cornfused.The application of logic to an illogical situation will likely result in 'cornfused'.... ;)

But let's consider......

This was his first listen to his first DIY speaker. Most n00bs are in a panic that their new baby may not even make a sound. So they're not particularily discriminating when it does play music, even if that music is a bit messed up.

Since he was unaware that the mid was out of phase, perhaps the destruction of the tweeter was related to his subconscious attempting to 'balance' the system using a higher power level.

m1ke323

10-03-2006, 01:57 AM

I think you guys are over analyzing the situation a little bit. The way I see it, is that I wired the midrange out of phase, possibly messed up the XO (I did double check it before I installed it though), and was kinda stupid when listening to it.

As I said before I was suprised how efficient these were, klipsh speakers get very loud with the horns so I was expecting the TMWW to be less efficient. I actually got the same volume out of the single TMWW speaker at -20db as I did with my 2 Klipsh at -5 to 0db. Granted there was a power difference because of the 4 vs 8 ohm speakers but still. The light that should have turned on to keep the volume in check, didn't light up in my head. I for some reason didn't even think about damaging the speaker, I just figured it would distort like every other speaker I have heard when it was turned up to loud. Instead of hearing distortion the tweeter dome just broke into a few pieces. I learned my lesson. I have another tweeter on the way and should get both speaker fully wired up and triple checked over within a week. I will let you guys know how it goes.

In reply to the speakers sounding good even though the mid was out of phase. This is my first speaker build besides a subwoofer and I wasn't really doing any critial listening. These was such a night and day difference between my Klipsh that I just sat there kinda amazed and not paying attention. That is when I got the idea to see how they would handle loud volumes. My guess is that the SPL was about 100db-110db for the few short times I would turn it up real high (15 seconds), but that is just a guess. I use to be into car audio so I am trying to use that as a frame of reference to guesstimate the SPL.

Just as Jonathanb's quote says "Experience is a hard teacher because she gives the test first, the lesson afterwards."

Thanks again for the help everyone. Despite this setback the speakers are looking amazing. I am pretty shocked how nice they look. I hope this is only the beginning to many more speaker building projects. A center up next and hopefully the Aerial Stryke Sub from Klone-Audio as well.

Mike

jonathanb3478

10-03-2006, 05:06 AM

I took the day off to finish up a whole lotta projects this weekend. I spent the morning with the Seas center channel. This one is a wrap. I changed a couple of resistor values slightly, but nothing that changes the basic character, and one of the changes is optional--it cools down the tweeter slightly.

...

I just figured I would ask...

Is the schematic with the referenced changes floating around somewhere, and I just have not found it?

Just curious, as the above quote was from 9/22.

jonathanb3478

10-03-2006, 05:11 AM

Despite this setback the speakers are looking amazing. I am pretty shocked how nice they look.

Please share with the rest of us!

And to paraphrase someone else:

You make these amazing speakers and don't even show us little thumbnails of a finished one.

:B

How did the iron on veneering go with your 2-ply backed veneer?

Dennis Murphy

10-03-2006, 09:51 AM

I just figured I would ask...

Is the schematic with the referenced changes floating around somewhere, and I just have not found it?

Just curious, as the above quote was from 9/22.

Hi I sent the revised schematics to Chuck. I don't know how to do nuthin' posting-wise. I'm a techno retard. Perhaps Chuck can post them. They certainly aren't a secret. Cheers.

chasw98

10-03-2006, 10:11 AM

Hi I sent the revised schematics to Chuck. I don't know how to do nuthin' posting-wise. I'm a techno retard. Perhaps Chuck can post them. They certainly aren't a secret. Cheers.

I have them at home. I will post them when I get home this evening after work.

m1ke323

10-03-2006, 12:38 PM

Jon, I will post pictures when they are completed or at least fully veneered. Right now I have part of the speaker done in my cherry veneer. So pictures will come when I am done veneering.

I will post pictures of my XO's too, I am just as proud of them as I am with my cabinets. They turned out really slick, those I can put pictures of right away.

Mike

m1ke323

10-03-2006, 05:01 PM

Here are some pictures of the crossovers I built. I left the stickers on most of the components until I know I have everything correct.

I hot glued and zip tied the components down and did all the soldering on the bottom of the board. I used adhesive rubber bumpers in the corners to make space for the wires on the bottom. Two screws through the board into the bottom of the cabinet will hold them in place.

I also have some pictures of the prototype speaker grills I made. These are made of steel where as the real ones will be aluminum. There will be 8 rods sticking out the back of the grill that will go into rubber sockets on the front of the speakers. The metal frame will also be covered in speaker grill cloth and attached under a lip on the back stide so it looks nice.

I made the grills to protect the speakers when I am not listening to them. These are in my living room which is also my current HT so I want some protection. If I ever am doing critical listening or watching movies, I can take them off easily.

Crossover:
http://aycu16.webshots.com/image/6095/2003742241049416846_rs.jpg (http://allyoucanupload.webshots.com/v/2003742241049416846) http://aycu32.webshots.com/image/2871/2003785865967141795_rs.jpg (http://allyoucanupload.webshots.com/v/2003785865967141795) http://aycu23.webshots.com/image/5342/2003784891499011318_rs.jpg (http://allyoucanupload.webshots.com/v/2003784891499011318)

I used crimp connecters for connecting to the terminal block, but I also soldered them once they were crimped. Not sure if it makes a difference, but it makes me feel better.

Prototype Seaker Grill:
http://aycu29.webshots.com/image/5708/2003784981381975236_rs.jpg (http://allyoucanupload.webshots.com/v/2003784981381975236)

Mike

ThomasW

10-03-2006, 05:07 PM

Looks good..... :T

With those screw down barrier strips, you'll want to put a small drop of hot glue on the top of each screw to make sure they don't vibrate loose....

m1ke323

10-03-2006, 05:25 PM

Thanks for the tip Thomas, I will do that.

I just can't get over the speaker grill. The thing feels like a football player can jump out of my projecton screen on Sunday and plow into the speaker and nothing will happen. haha

chasw98

10-03-2006, 06:48 PM

Here it is. Dennis has blessed this crossover as the "1" for using the Seas 27TBFC/G tweeter to match the WWMT's he designed the XO for.

http://i21.photobucket.com/albums/b297/chasw98/Chuck%20CC/sc_0002.gif

http://i21.photobucket.com/albums/b297/chasw98/Chuck%20CC/sc_0001-NOL2021.gif

http://i21.photobucket.com/albums/b297/chasw98/Chuck%20CC/sc_0000.gif

The only changes he suggests were to decrease the resistance of the 12 ohm resistor (R3041) in the tweeter circuit to 10 ohms. It will make a difference in how "bright" it sounds. I built it both ways and prefer the 10 ohm variety. I have both images and attachments for those that neeed them.

Igor, DM's helpful assistant ;x(

cobbpa

10-03-2006, 07:43 PM

I see only a few resistors on your actual crossovers...are that many really taken care of by the neighboring inductor values? You had more on the original one you posted. It also looks like an inductor was added, correct?
Just nailing down specifics!

chasw98

10-03-2006, 08:30 PM

OK, the low freq XO has not changed.

The mid has changed this way:
C2011 (C2) used to be 57 mf, is now 55 mf. Not critical according to DM.
R2031 (R4) 1 ohm - no change.
R2051 ignore.
L2051 (L3) used to be 1.2 mh, is now 1.5 mh.
R2021 (R3) 40 ohms - no change.
L2021 (L2) 2.0 mh is removed.
R2041 (R5) used to be 17 ohms, is now 15 ohms. Not critical according to DM.
R2061 (R6) 1 ohm - no change.
L2061 (L4) .1 mh - no change.
C2061 (C3) 3.3 mf - no change.

The tweeter has changed this way:
C3011 (C1) used to be 10 mf, is now 8.2 mf. <EDIT>
R3031 (R2) 3 ohms - no change.
R3021 (R1) 8 ohms - no change.
L3021 (L1) 1.2 mh - no change.
R3041 added to the XO across the tweeter 12 or 10 ohms depending upon taste.

The bracketed values are from the original RS28 schematic for reference.

HTH

Chuck

Jim Holtz

10-03-2006, 08:53 PM

OK, the low freq XO has not changed.

The mid has changed this way:
C2011 (C2) used to be 57 mf, is now 55 mf. Not critical according to DM.
R2031 (R4) 1 ohm - no change.
R2051 ignore.
L2051 (L3) used to be 1.2 mh, is now 1.5 mh.
R2021 (R3) 40 ohms - no change.
(L2) 2.0 mh is removed.
R2041 (R5) used to be 17 ohms, is now 15 ohms. Not critical according to DM.
R2061 (R6) 1 ohm - no change.
L2061 (L4) .1 mh - no change.
C2061 (C3) 3.3 mf - no change.

The tweeter has changed this way:
C3011 (C1) used to be 8.2 mf, is now 10 mf.
R3031 (R2) 3 ohms - no change.
R3021 (R1) 8 ohms - no change.
L3021 (L1) 1.2 mh - no change.
R3041 added to the XO across the tweeter 12 or 10 ohms depending upon taste.

The bracketed values are from the original RS28 schematic for reference.

HTH

Chuck

Hi Chuck,

Unless I'm reading the tweeter crossover wrong, C3011 is now 8.2 Mh. Is that correct?

Also, isn't R2051 the DCR for L2051 on the mid? If not, what is the suggested DCR of the the inductor.

Sorry to pepper you with questions. ;) Maybe Dennis will hop in and take the heat off you. :D

Jim

hohe2112

10-03-2006, 09:19 PM

OK, the low freq XO has not changed.

I went back and looked at the original schematic for the RS28 version on page 1. Altough the component values are the same, the DCRs are different (much smaller on the original). In fact the 4.7mH inductor on the original calls for a steel laminate with a .231 ohm DCR and the new schematic shows 0.5 ohm. I did some quick looking and found a 14awg Erse Perfect Lay at Zalytron with a DCR of 0.558 ohm. If the new schematic is correct I think I'd rather go this route and avoid any steel laminates.

The new schematic doesn't specify which resistors are inherent DCR values. I think I can make educated guesses, but something a bit more concrete would probably be of much greater benefit to the group at large :B

Thanks again to Dennis and Chuck for getting this out. As you can see, there are a few of us who have been chomping at the bit for it. In my case, I've been waiting to do an Uber buy with PE, Zalytron, and Madisound to get my new front end (LCR) started. I've got Thanksgiving week off (a WHOLE week!) and I know exactly how I'm going to spend it! ;)

Mike

chasw98

10-03-2006, 09:20 PM

Hi Chuck,

Unless I'm reading the tweeter crossover wrong, C3011 is now 8.2 Mh. Is that correct?

Also, isn't R2051 the DCR for L2051 on the mid? If not, what is the suggested DCR of the the inductor.

Sorry to pepper you with questions. ;) Maybe Dennis will hop in and take the heat off you. :D

Jim

No, Master Dennis has left Igor here to deal with it, I think.

You're right C3011 is 8.2 and used to be 10mf. (Igor not htinking straight).
I will change the original post.
R2051 is the DCR and can be ignored as far as putting a resistor in there.

chasw98

10-03-2006, 09:25 PM

I went back and looked at the original schematic for the RS28 version on page 1. Altough the component values are the same, the DCRs are different (much smaller on the original). In fact the 4.7mH inductor on the original calls for a steel laminate with a .231 ohm DCR and the new schematic shows 0.5 ohm. I did some quick looking and found a 14awg Erse Perfect Lay at Zalytron with a DCR of 0.558 ohm. If the new schematic is correct I think I'd rather go this route and avoid any steel laminates.

The new schematic doesn't specify which resistors are inherent DCR values. I think I can make educated guesses, but something a bit more concrete would probably be of much greater benefit to the group at large :B

Thanks again to Dennis and Chuck for getting this out. As you can see, there are a few of us who have been chomping at the bit for it. In my case, I've been waiting to do an Uber buy with PE, Zalytron, and Madisound to get my new front end (LCR) started. I've got Thanksgiving week off (a WHOLE week!) and I know exactly how I'm going to spend it! ;)

Mike

When I sent Dennis the XO I didn't change anything on the low end. I used a steel laminate that was a little over in value and rewound it to what the circuit called for.
I am the one who has been chomping and I just thought it might speed it up to help Dennis and take some load off of him. I think he has a life unlike some of us :B

WillyD

10-04-2006, 05:57 PM

Hmmmm...A xover for the 27TDFC. This would match my 27TDFC MTs well, right?

chasw98

10-04-2006, 06:06 PM

Hmmmm...A xover for the 27TDFC. This would match my 27TDFC MTs well, right?

I am running the M/T's for surround and they match up beautifully!

Dennis Murphy

10-04-2006, 08:47 PM

No, Master Dennis has left Igor here to deal with it, I think.

You're right C3011 is 8.2 and used to be 10mf. (Igor not htinking straight).
I will change the original post.
R2051 is the DCR and can be ignored as far as putting a resistor in there.

Thanks for standing in, Igor. I was detained by a band of unruly citizens with torches. Don't sweat the dcr on the big woofer coil. A steel laminate is fine. It's not critical. I just put in a rough approximation. I should have used the same value as for the RS version. Resistance variations are much more critical in the shunt circuits. The resistors that represent dcr, and aren't real, are 1011, 1031, and 2051. Also, after rechecking some measurements, you can eliminate inductor 2021 in the mid circuit. All you need is the 40 ohm resistor. The coil doesn't pass a cost-benefit test. Sorry Chuck--could you make that change? Thanks!

chasw98

10-04-2006, 10:05 PM

Change made with correct schematic.

Dennis Murphy

10-04-2006, 10:16 PM

Yes, Master, change made!
L2021 is equal to L2 which used to be 1.2 Mh. Correct?

Hmmm. I'm not sure what you mean by "used to be." It was 0.2 mH on the circuit I sent you and you posted. I don't remember what it was with the RS tweet. But I must return to the cemetary.

WillyD

10-04-2006, 11:11 PM

I am running the M/T's for surround and they match up beautifully!

Must..not..spend anymore $$$. :twisted:

Would this xover cost about $100? I tried throwing together a BOM last night, but was busy writing a paper.

Also, when you say ignore R0251, do you mean it isn't necessary anymore?

jonathanb3478

10-05-2006, 04:05 AM

Here it is. Dennis has blessed this crossover as the "1" for using the Seas 27TDFC tweeter to match the WWMT's he designed the XO for.

Hmm...

I was under the impression that this newly designed Seas tweeter center would use the same tweeter as the DM Seas TMWW, namely the 27TBFC/G.

I do not see the bennefit of using the tweeter many of us will be using for surround duty (27TDFC - Modula M/T), vs matching the tweeter used in the mains (27TBFC/G - DM Seas TMWW).

It just seems to me that if this was a mistaken post of which tweeter was used in this new center XO design, it would have been caught before now.

I do not understand why the 27TDFC was used. :confused:

chasw98

10-05-2006, 05:43 AM

Hmm...

I was under the impression that this newly designed Seas tweeter center would use the same tweeter as the DM Seas TMWW, namely the 27TBFC/G.

Correction made. Good eyes!

WillyD

10-05-2006, 08:42 AM

Correction made. Good eyes!

http://www.htguide.com/forum/showpost.php4?p=188417&postcount=93

The 27TDFC and 27TBFC are essentially "interchangeable". They're NOT interchangeable with the RS28a, which has a substantially different impedance (about 3.5 ohms, versus ~ 6 ohms). The first crossover is suitable for either of the Seas models - the second crossover is explicitly for the RS28a. ~Jon

I believe this would apply to the WMTW as well correct? :T

chasw98

10-05-2006, 08:50 AM

http://www.htguide.com/forum/showpost.php4?p=188417&postcount=93

I believe this would apply to the WMTW as well correct? :T

I am not sure anymore. Igor feel very confused :confused: :crazy:

jonathanb3478

10-05-2006, 10:15 AM

Correction made. Good eyes!

It seems that things that seem to me to be, may not be. Or something. Thanks for the clarification, Chuck. :T

The 27TDFC and 27TBFC are essentially "interchangeable". They're NOT interchangeable with the RS28a, which has a substantially different impedance (about 3.5 ohms, versus ~ 6 ohms). The first crossover is suitable for either of the Seas models - the second crossover is explicitly for the RS28a. ~Jon

I KNEW IT!. I thought I read that somewhere, but when I later looked for it again to confirm, all I found was a spot on ZaphAudio.com where he mentions:

Rumor has it the Seas 27TDFC is a drop in upgrade for the 27TFFC.

So it seems to me...

uh

nevermind.

:D

Dennis Murphy

10-05-2006, 10:27 AM

Must..not..spend anymore $$$. :twisted:

Would this xover cost about $100? I tried throwing together a BOM last night, but was busy writing a paper.

Also, when you say ignore R0251, do you mean it isn't necessary anymore?

As for 2051, it never was necessary. That's just the approximate dcr of the 1.5 coil. I think this puppy will cost more than $100 once you start adding up the inductors. That's why I eliminated one of them. And if you insist on poly caps all around, I'm sure it would be well over $100.

WillyD

10-05-2006, 01:10 PM

Post #1417 has the newest BOM.

Dennis Murphy

10-05-2006, 01:37 PM

As for 2051, it never was necessary. That's just the approximate dcr of the 1.5 coil. I think this puppy will cost more than $100 once you start adding up the inductors. That's why I eliminated one of them. And if you insist on poly caps all around, I'm sure it would be well over $100.

Ooops I wasn't thinking. I automatically assumed two crossovers for a stero pair. But this, heeeeeeyuk, is a center channel. Now I git it. So you should be able to come in under $100.

WillyD

10-05-2006, 03:52 PM

Ooops I wasn't thinking. I automatically assumed two crossovers for a stero pair. But this, heeeeeeyuk, is a center channel. Now I git it. So you should be able to come in under $100.

:D

You had me scared for a second. :E

The total price in the BOM I just made was $93. I bet the cost could be reduced even futher, but it seems farily reasonable to me (assuming it is correct). 8)

Fryguy

10-05-2006, 07:26 PM

What size female disconnects are required for each of these speakers?

cobbpa

10-05-2006, 07:35 PM

:D

You had me scared for a second. :E

The total price in the BOM I just made was $93. I bet the cost could be reduced even futher, but it seems farily reasonable to me (assuming it is correct). 8)

My checklist was slightly different, since I bought based on the preliminary design, but yours looks right to me! Just thought I'd verify :T

WillyD

10-05-2006, 11:32 PM

My checklist was slightly different, since I bought based on the preliminary design, but yours looks right to me! Just thought I'd verify :T

Thanks. :T

If I hadn't just spent close to $700 on this sub I am building, I'd be building this thing immediately. I actually have zero center right now, so moving up to this baby would be niiiice. :)

Jim Holtz

10-06-2006, 06:09 AM

What size female disconnects are required for each of these speakers?

I don't have any RS drivers that aren't mounted but I believe that they take 1/4" spades and the 27TBFC/G takes the smallest size whatever that is. Check Madisound and you'll be covered.

Jim

Brian Bunge

10-06-2006, 07:16 AM

The 1/4" spades are actually a little too large. I use whatever the next size down that PE sells (I think they're like .2" or something) and even then still have to compress them down a bit to make them fit snugly.

Jim Holtz

10-06-2006, 09:17 AM

atm98

10-06-2006, 01:10 PM

WillyD,
I looked over your BOM (I am planning to copy it). I don't see the L2051. Also, why is L2061 1.2mH and not 0.1?

WillyD

10-06-2006, 04:40 PM

WillyD,
I looked over your BOM (I am planning to copy it). I don't see the L2051. Also, why is L2061 1.2mH and not 0.1?

Hey atm, thanks for checking the bom for errors.

I don't know how I managed to leave out L2051, but it is there now. I used the 1.5mH 15ga Jantzen coil which looks like it is satisfactory.

For L2061, I had actually put the correct description, part number, and price down. The 1.2mH was a typo, it is changed now. Please go over it again to make sure there are no more mistakes. I would certainly appreciate it. :T

ifeliciano

10-06-2006, 09:20 PM

Hey atm, thanks for checking the bom for errors.

I don't know how I managed to leave out L2051, but it is there now. I used the 1.5mH 15ga Jantzen coil which looks like it is satisfactory.

For L2061, I had actually put the correct description, part number, and price down. The 1.2mH was a typo, it is changed now. Please go over it again to make sure there are no more mistakes. I would certainly appreciate it. :T

WillyD,

If not already done, you should edit your prior post with the center channel seas BOM...just to avoid confision :E

WillyD

10-06-2006, 10:05 PM

Good call. ;)

Fryguy

10-06-2006, 11:48 PM

Brian Bunge

10-07-2006, 07:41 AM

Spades?? They aren't female disconnects?

Well, technically yes. Jim said spades and I was responding to that. They are female disconnects.

agrippa

10-08-2006, 06:14 PM

Wow... I have watched this one for awhile now. I posted about a year ago with a similar design concept desire. It looks like this is close to what I was looking at with a curved box. I am saving up for the best set of speakers I can get for under $1000. My experience has been with the $10 and under tweeters and mids, cheap cheap xovers, and the $20 and under woofers. This is to be my leap into true top end sound. I have the RS225s allready.
Here is my question though:
It appears that there are two main design concepts here centerred on the tweeter,
one with the popular Seas 27TDFC at about $29 and the other is Dayton RS28A4 at $47. Correct? (ok there is the ported vs closed too)
What happens if the tweeter was say a Scan-Speak 9500 at $87, or even a Hiquphon OW1 at $100? Or how about the Peerless 810921 ($59), Vifa XT25 ($54), Morel MDT33 ($95)?
What would I gain by spending a bit more? Is this a case of dimishing return or is the Seas 27TDFC just that good and it is in the same league as the above mentioned?
The 5 tweeters I included seem to get alot of play around the net in DIY high end speakers. I have looked at several tests around the net on these also. Does anyone know what the sound difference could be?

Would any mate poorly with the RS drivers?

Also, I am a bit concerned with the RS28's build quality. They seem to very inconsistant in performance.

I thought the thread should be a bit longer. :)
Thanks for any crazy thoughts. If this dosn't belong here just tell me to get lost.

m1ke323

10-08-2006, 07:00 PM

Ray_D

10-08-2006, 08:17 PM

Dennis Murphy

10-08-2006, 08:47 PM

I am very new at speaker building and know no such thing about actually designing the speaker. However I do know that you can't just drop in another tweeter and expect to keep the current XO design.

The crossovers are driver specific and you would be ruining the speaker if you tried to deviate from the RS28 or Seas tweeter.

Right you are. Tweeters vary widely in frequency response, complex impedance, and sensitivity. Crossovers need to address each of these parameters.

agrippa

10-08-2006, 09:25 PM

"I am very new at speaker building and know no such thing about actually designing the speaker. However I do know that you can't just drop in another tweeter and expect to keep the current XO design."

Yup... I knew this. My question is how do the drivers stack up. If I were to try a different tweeter I would have to come up with a different x-over. I was working with someone else on a similar design... He went with morel supremes... THat may be a bit out of my price range. I may be able to stomach the Scan speak 9500 though.

"check out http://206.13.113.199/ncdiyaudio/mark/index.htm"

Book marked and one of my favorites along with http://zaphaudio.com/

I am wanting to know does the price equal performance? Clearly the seas is a great buy and seems to be better than most drivers in it's price range. The RS28 is also great with some consistency problems pointed out by Mark on his web site.

It is hard to invest major bucks/time into a project and when you are done feel "oh it would have been better if I had gone with the Scan speak or morel or something". I am hoping that this will knock my Paradigm Monitors to the bed room or ebay. All my experience in speaker building has been building speakers for people's shops, rec roms, or dorm rooms. Nothing in this range. (see my 1st post)

I am fishing for opinions on tweeters. Example: The Seas 27TDFC is far superior to say any goldwood tweeter making the $30 cost vs the $6 cost a good investment. You easly get what you are paying for. However, Is the Scan speak 9500 far superior to the seas or is the superiority only slight...
The Frequency response on the scan speak looks slightly better but does it sound slightly better... I have never heard any of these.

Ramble...Ramble...oh, sorry I am tired (I taking care of a sick baby girl). I will try and collect my thoughts and present it more clearly later if needed.

Dennis H

10-09-2006, 12:04 AM

I am wanting to know does the price equal performance? Nope.

jonathanb3478

10-09-2006, 03:31 AM

It appears that there are two main design concepts here centerred on the tweeter, one with the popular Seas 27TDFC at about $29 and the other is Dayton RS28A4 at $47. Correct?

Incorrect. No one has mentioned it already, but the tweeter is the 27TBFC/G. It runs ~$33 at Madisound. It is the same as the 27TDFC, except for the dome material used. The TBFC/G is a metal dome, the TDFC is a soft dome. This should be easy to remember, as all the drivers in this project use metal diaphragms.

What happens if the tweeter was say a Scan-Speak 9500 at $87, or even a Hiquphon OW1 at $100? Or how about the Peerless 810921 ($59), Vifa XT25 ($54), Morel MDT33 ($95)?

What would I gain by spending a bit more? Is this a case of dimishing return or is the Seas 27TDFC just that good and it is in the same league as the above mentioned?

You point out www.zaphaudio.com in a later post. Some of the tweeters you mention are directly compared in the tweeter measurement article on that site. Based on the results, I would say that in most cases you get very little for your money. Certainly not enough to justify the price increase over the 27TBFC/G, for me. The consistency issues people talk about regarding the RS28a take if off my list, also. If it was the one that was ~$15 less than the Seas, then maybe. Until/unless that happens, I will stick with the cheaper TBFC/G or TDFC, personally.

You will also need to consider the cost of time and materials for making a completely new crossover for a new tweeter, as well. Also, you will need to think about whether your crossover will even get as much out of a costlier tweeter, than Dennis Murphy's design gets out of the TBFC/G. I would not assume it would, if I were you.

Good luck with what ever you decide!

Brian Walter

10-09-2006, 11:19 AM

What happens if the tweeter was say a Scan-Speak 9500 at $87, or even a Hiquphon OW1 at $100? Or how about the Peerless 810921 ($59), Vifa XT25 ($54), Morel MDT33 ($95)?
What would I gain by spending a bit more? Is this a case of dimishing return or is the Seas 27TDFC just that good and it is in the same league as the above mentioned?

I'll make a few comments that haven't been made yet. To start with, those are all good tweeters and when properly used will result in very good sounding speakers. I think it would be safe to say that each tweeter has it's strong points and own signature sound, so which you prefer is more or less a personal opinion. I'm not sure if the Hiquphon tweeter is a viable option as it needs to be crossed fairly high, but a good designer can probably make it work.

I have personally listened to well designed speakers using the Scan-Speak, Hiquphon, Seas, and Dayton tweeters, but not the others. If you like a lot of high end sparkle, you would prefer the Seas 27TDFC over the Dayton or 27TBFC/G?, but the Dayton has more weight to it and the 27TBFC is somewhere in between. Keep in mind, this is my opinion, others may not agree. The Scan-Speak is also a very smooth tweeter, similar to the Dayton, but is more extended, so it may be a better choice for this combination of drivers, but it costs more and the crossover would need to be revised. I used the Seas 27TBFC/G metal dome and I am very happy with it. For me it provides a perfect combination of extension and weight.

If you can make it to the Iowa DIY event coming up at the end of the month, I'm sure you will have an opportunity to listen to several of these tweeters in various speakers. There are other events coming up as well, so depending on where you live, there may be one close by. But keep in mind, the crossover has a lot to do with the sound of the tweeter, so comparing tweeters in different designs may not tell you what you really want to know.

Brian Walter

agrippa

10-09-2006, 12:06 PM

o.k.
I went back to www.zaphaudio.com and I agree. After staying up all night long with the sick kid and looking at the data I feel more comfortable making this leap. I can say good bye to my $5 daytons tweeters and $7 vifa/jbl buyout midwoofers. Maybe not good buy as I still have apile of cheap speaker parts that need a home.

This apears to be purchase list for Denis Murphy's x-over. Correct?
http://www.htguide.com/forum/showpost.php4?p=271455&postcount=1036

One last thing:
Does anyone know how the curved cab compairs to the normal cab? Is their much difference in performance? Also, does several layers of luan provide a sonicly dead cabinet? Luan from Home Depot seems to have consistantcy problems. I think I will order it from a better lumber yard if I go with the curved cabs.

The reason I ask about all this is that I happen to have 8 Rs225s and I may be able to build 4 cabs and give my parents (Dad) a great Gift. :). He can get rid of his Bose Cubes which he regrets buying. I just want to get this right.
Thanks. Great thread.

agrippa

10-09-2006, 12:34 PM

Ha! I found some info on the rounded cabs.
http://www.htguide.com/forum/showthread.php4?t=15323&page=34&pp=35

agrippa

10-09-2006, 12:51 PM

If you like a lot of high end sparkle, you would prefer the Seas 27TDFC over the Dayton or 27TBFC/G?, but the Dayton has more weight to it and the 27TBFC is somewhere in between. Keep in mind, this is my opinion, others may not agree. Brian Walter

Do you need to change the x-over if you go with the TDFC over the TBFC?

If you can make it to the Iowa DIY event coming up at the end of the month, I'm sure you will have an opportunity to listen to several of these tweeters in various speakers.
Brian Walter

When and where in Iowa? I live in Minnesota

Jim Holtz

10-09-2006, 01:46 PM

Do you need to change the x-over if you go with the TDFC over the TBFC?

When and where in Iowa? I live in Minnesota

The Iowa DIY Speaker event will be held October 28th in Altoona, Iowa which is a suburb of Des Moines. Send me an email and I'll get you on the email list with all of the info.

You'll get to hear, Modula M/T's, Natalie P's, RS 3-ways (Seas version) and many other speakers that are based on everything from Usher to Accuton drivers. Plus we're having a Super Budget class that should be a lot of fun.

Jim

Jim Holtz

10-09-2006, 04:34 PM

Well, technically yes. Jim said spades and I was responding to that. They are female disconnects.

Thanks Brian. I did mean to say female disconnects but it came out spades. Oldsheimers.... :confused:

Jim

m1ke323

10-09-2006, 04:45 PM

atm98

10-09-2006, 05:48 PM

Hey atm, thanks for checking the bom for errors.

I don't know how I managed to leave out L2051, but it is there now. I used the 1.5mH 15ga Jantzen coil which looks like it is satisfactory.

For L2061, I had actually put the correct description, part number, and price down. The 1.2mH was a typo, it is changed now. Please go over it again to make sure there are no more mistakes. I would certainly appreciate it. :T

WillyD,
The rest of the list looks fine. Another Question: Why 18ga and 15ga inductors? Wouldn't you get better performance or power handling out of a heavier gage? Or is dcr the only factor we have to account for? Obviously a cost/benefit issue, but I could use some help understanding the tradeoff.

Austin

WillyD

10-09-2006, 06:11 PM

Well, the 18ga inductors are aircores, have the correct DCR (or less), and are already rated for 300W RMS.

Concerning the .1mH inductor for the mid...I guess if you felt so inlclined, you could use some 16, 14, or even 12ga Goertz copper foil inductors from Madisound, but from what I understand, that wouldn't be necessary. Same goes for the 1.2mH 18ga inductor for the tweeter.

The 4.7mH and .55mH indcutors on the woofer circuit (16ga and 15ga respectively) are both rated for 500W RMS power handling.

Like you said, its a cost/benfit issue, and I think a lot of the folks here don't spend extra money unless it is really worth it. Sure, you could go crazy and buy all 12ga air core inductors, but you'd end up spending close to double (most likely).

Brian Bunge

10-09-2006, 06:14 PM

After seeing how the copper foil inductors can carrode over time I definitely don't see myself buying any of those ever again.

WillyD

10-09-2006, 06:39 PM

After seeing how the copper foil inductors can carrode over time I definitely don't see myself buying any of those ever again.

I guess price isn't the only reason to "avoid" them, eh? ;)

Fryguy

10-09-2006, 07:30 PM

See http://fryguy.nevercontent.com/DaytonProject for what I believe to be the optimal price/performance configuration of the seas TMWW towers.

These are what I'm building. I'll let you guys know soon enough how well they work.

agrippa

10-09-2006, 09:25 PM

agrippa, if you use the curved plans by Brian Walter which have a 18" radius, 1/4" luan from HD won't make the bend. The only thing HD sells that will make the radius is their 1/8" mdf handypanel sold in 2x4 sheets, I used a layer of this around the entire cabinet.

The 3/8" bending ply I used from a local lumber yard actually made the bend easier then the 1/8 mdf from HD despite being 3 times as thick. I would recommend you use something designed to bend, it makes it alot easier. This is what bending ply can do:

1. Thanks, I will look into it. Is the ply as dead as the 1/8 MDF in layers?

2. It was said that the TDFC has more sparkle. Do you need to change the x-over if you go with the TDFC over the TBFC?

thanks... I am getting excited about this. I am driving my wife nuts. It will cost me a new stove I suppose.

m1ke323

10-09-2006, 09:57 PM

1. Thanks, I will look into it. Is the ply as dead as the 1/8 MDF in layers?

The 3/8" bending ply I used made a very dead cabinet. I ended up using 2 layers of 3/8" ply and 2 layers of the 1/8" mdf handypanel. My cabinet is an 1" at its thinnest point and 1-5/8" at its thickest. Good luck :T

Mike

agrippa

10-09-2006, 10:16 PM

Brian Walter

10-09-2006, 11:32 PM

m1ke323
I went back and looked at your posts on the curved design. I download every pic I could find. Man they look nice. How did you get that steel template made? I may have to do the same but I would have to go with something like handypanel for a template. I figure I am making 4 boxes.

You can get by with a template made from MDF. I will be handing out plans for my speakers at Iowa and you can simply glue the paper pattern onto a sheet of MDF and then cut close to the lines and sand till perfect. From then on all you need to do is cut out the rough shape with a hand held jig saw and use the router with a pattern bit to finalize each shelf.

As far as substituting the 27TDFC for the 27TBFC/G, Jon Marsh said it could be done on some of his designs, but Dennis Murphy never tried it on his, so he has been hesitant to say yes. I would think it would be really close to a direct replacement, but you may want to adjust the tweeter padding slightly. If I recall correctly, Jon said the difference between the TDFC and the TBFC/G is probably less than the difference from lot to lot of either tweeter.

I am also from Minnesota and I believe Mike is now as well, maybe we should organize a Minnesota get-together sometime?

Brian Walter

agrippa

10-10-2006, 08:46 AM

I will be handing out plans for my speakers at Iowa and you can simply glue the paper pattern onto a sheet of MDF and then cut close to the lines and sand till perfect.

cool

If I recall correctly, Jon said the difference between the TDFC and the TBFC/G is probably less than the difference from lot to lot of either tweeter.

O.k. I will stick with the TBFC.

I am also from Minnesota and I believe Mike is now as well, maybe we should organize a Minnesota get-together sometime?
Brian Walter

I live in the great uncharted north... up by Bemidji where I work. I will try really hard to get to Iowa. We can talk there. :)

atm98

10-10-2006, 11:10 AM

Need Advice:
I have drawn up cabinet plans using MDF/Oak Plywood. The idea being to not veneer.

Plywood for the top, front, sides.
MDF for the back, bottom, internals, baffle back.
The ¾” corners will be hardwood oak with a rollover.

In my precise research at Lowes and HD, I tapped on a few wood options. The MDF sounds very dead compared to the other options. So my question is how will the oak plywood affect the sound quality? Can I lessen the effect with filler material? If so, will I need to make the cabinet larger due to the additional fill material?

I have notice other DIY builders using plywood, for example:
Anatomy of a Natalie-P / Modula MTM Tower
John W’s Modula MT 3/4” using Baltic birch plywood
Someone’s CJD (Chris) MTM RS150

However, I have been unable to get a definitive answer on the plywood’s effect.

Any advice or recommendations will be helpful.

BobEllis

10-10-2006, 01:56 PM

Need Advice:
...The MDF sounds very dead compared to the other options...

Now you know why MDF is so popular. ;)

In my oak days I built the cabinet in MDF with 1/4" oak ply glued on before cutting, rabbeted the corners to accept the solid oak molding and sanded flush. Home Depot oak ply is cheaper than buying paperbacked veneer.

agrippa

10-10-2006, 02:26 PM

simple test
Take 3/4" MDF and 3/4" Plywood and rap on it will your knuckels while you listen from the other side. Which one transfers sound less? MDF...but Baltic Birch is good also. I would rather work with the birch but MDF is hard to beat for sound. MDF is dangerous to work with. I wear a resperator and eye protection...DARTH VADER.
The guys who made the curved boxes used plywood and MDF in combination. Check out their posts
Brian Walter's curved cabinet plans & pics are below. His seem to be of high quality.
http://www.htguide.com/forum/showth...5335#post265335
http://www.htguide.com/forum/showth...5338#post265338
http://www.htguide.com/forum/showth...6741#post266741
He might be able to answer your questions on the effect of Plywood

saweetnesstrev

10-11-2006, 09:25 PM

Brian Walter

10-12-2006, 12:46 PM

Any advice or recommendations will be helpful.

I don't think I am any more qualified to answer your questions or to give you advice than many others around here, but I'll try. You can make high quality cabinets out of either plywood or MDF. Baltic Birch plywood is better than your run of the mill plywood, as it has very little if any voids in the ply's and the ply's are also made of hardwood, where as with typical hardwood plywoods, only the veneer is hardwood.

As you noted, plywood does ring a little more than MDF, but proper bracing and sound deadening materials minimize this. Typical sound deadening materials are usually sheet goods such as roofing felt, vinyl flooring or commercial acoustic damping pads, such as BlackHole, but a troweled on mixture of plaster and other materials seems to work as well. Open cell foam, polyfill and fiberglass offer some damping qualities if glued to the surface, but are primarily intended to reduce the back wave from the speaker cone from reflecting off of the inside wall surfaces and back through the speaker.

Open cell foam, polyfill and fiberglass do not reduce the effective volume of a cabinet, but solid materials like roofing felt, vinyl flooring, goop or modeling clay will, as do internal braces.

I personally like using a combination of 1/4" plywood and 3/4" MDF similar to what Bob Ellis suggested because it seems to work well and as he said, the 1/4" plywood is cheaper than veneer. If you could apply a viscous layer of glue between the 3/4" MDF and 1/4" plywood you would increase the damping qualities of the panel considerably, or at least that has been my experience.

Brian Walter

ibilisi

10-12-2006, 03:55 PM

Would you recommend this speaker design for a newbie with his dad a repair guy and my neighbor and dad a wood worker,, and what plans would be good for me cause theres like 3 or more of the same kind..

also would it be compatible with a pioneer 802 receiver?

Thanks Trev.

I would suggest going to page one, looking at the first post and clicking the link to the overview. You'll learn a lot and most likely most of your questions will be answered.

As far as the Pioneer goes, check the specs, if it can drive 4ohm speakers you "should" be fine. There are always caveats that apply.

atm98

10-13-2006, 12:31 PM

Thanks for everyone's advise. I plan on using Birch for the top, sides and front. On the inside I will glue the roofing felt to the exposed plywood. This should help the box resonance issue. I will also use fiberglass for the reflected wave issue. I do have a question about time-alignment that I will post next. Thanks again.

Austin

ThomasW

10-13-2006, 02:10 PM

Roofing felt is used between laminated layers of wood to create constrained layer damping. Simply putting it on the interior surface won't do anything.

BTW why don't you simply start a thread about your project and ask your questions there? Posting questions about your project onto a 40 page thread means the info gets lost. If you start a project thread we can later link to it.... :T

atm98

10-13-2006, 02:24 PM

ibilisi

10-19-2006, 03:01 PM

Quick question, I've decided after much delay(months - hey, had no time) to build the seas version of the front three (cabs nearly built - not finished).

I have a question on the center xo - at position R2021, which calls for one 40ohm resistor. I am currently trying to build all xo with mills resistors and since there is no 40ohm option available, would it be better to place 2x82 ohm resistors in parallel or 2x20 in series? OR use the 47 ohm mills resistor instead?

Also any word on Dayton v. Solen caps?

Thanks in advance

ThomasW

10-19-2006, 04:47 PM

Use a pair of resistors, that doubles the power handling.

Between those 2 brands of caps just toss a coin.

Jim Holtz

10-19-2006, 05:09 PM

Also any word on Dayton v. Solen caps?

Thanks in advance

I agree with Thomas completely. I'd also toss out Jantzen caps which are slightly less expensive than Solens but a bit more than Dayton. They have a very smooth sound to my ears. I like them and use them when they fit my needs.

My $.02 worth. :D

Jim

Dennis Murphy

10-19-2006, 06:56 PM

[I have a question on the center xo - at position R2021, which calls for one 40ohm resistor. I am currently trying to build all xo with mills resistors and since there is no 40ohm option available, would it be better to place 2x82 ohm resistors in parallel or 2x20 in series? OR use the 47 ohm mills resistor instead?

Definitely go with parallel 82's. Don't even think about a series solution. The main advantage of Mills is that they don't take up as much space. But sound-wise, there's no difference. I use Dayton caps, FWIW.

ibilisi

10-20-2006, 09:13 AM

Thanks for the quick feedback guys!

In sum, if you are going Mills go parallel 82s.

Caps: For all intensive purposes all options are fairly equal. Spend as much as you want or as little. Jantzen might be that nice middle-ground.

Dennis H

10-20-2006, 12:54 PM

Don't even think about a series solution. Errr, why?

BigJim_inFLA

10-20-2006, 10:31 PM

I finally finished my center channel!! This is the DM version using the RS28. It was my first try at veneering but I must say it went pretty easy. I haven't given it a thorough listen yet, it's late and my downstairs neighbors already don'r like me. :B I'll let you know how I like tomorrow! And if anyone has suggestion for getting a good picture of a gloss black baffle with artificial light I'd like to hear them. Another question...for those building these sealed, besides lining the walls with foam are you filling them at all?

Jim

Inu_Yasha

10-21-2006, 03:56 AM

Wow, very nice job! I'm debating on weather or not to do a paino black for my baffle. How long did it take to do the black baffle?

kano32

10-21-2006, 04:05 AM

Very nice job! Let us know what you think of the sound.

wkhanna

10-21-2006, 09:13 AM

Your veneer looks fabulous, BigJim!

If that was your first attempt at using it, you should be very pleased!

BigJim_inFLA

10-21-2006, 10:46 AM

Thanks guys. :B

I'm debating on weather or not to do a paino black for my baffle. How long did it take to do the black baffle?

It took three weeks in total, although most of that was because of class and bad weather. I used lacquer and it will blush when sprayed in high humidity, and I live in central Florida so we always have high humidity. I think I actuall spent about 8 hours for the spraying and sanding. In truth I haven't sanded the last coats of clear yet, I need to let them dry for a bit and couldn't wait to hear it so I put it together as is, but it looks good the way it is. In another week or so I'll pull out the drivers and sand and polish the baffle. I've got 9 coats of black and 6 coats of clear. I used spray cans and sanded between every three coats. I started with 400, then 600 for the black and used 1000 grit on the clear. Whwn I finish it will be with 1500 and 2000 then rubbing compound and polish.

Jim

Inu_Yasha

10-21-2006, 12:51 PM

Thanks guys. :B

It took three weeks in total, although most of that was because of class and bad weather. I used lacquer and it will blush when sprayed in high humidity, and I live in central Florida so we always have high humidity. I think I actuall spent about 8 hours for the spraying and sanding. In truth I haven't sanded the last coats of clear yet, I need to let them dry for a bit and couldn't wait to hear it so I put it together as is, but it looks good the way it is. In another week or so I'll pull out the drivers and sand and polish the baffle. I've got 9 coats of black and 6 coats of clear. I used spray cans and sanded between every three coats. I started with 400, then 600 for the black and used 1000 grit on the clear. Whwn I finish it will be with 1500 and 2000 then rubbing compound and polish.

Jim

You and I are in the same situation. My family lives on the water in alabama, so it's always humid out, and I go to the University of Alabama in northern Alabama.

What brand of spay paint and laquer did you use? Also, did you wet or dry sand?

BigJim_inFLA

10-21-2006, 01:05 PM

What brand of spay paint and laquer did you use? Also, did you wet or dry sand?

I used American Tradition gloss black and gloss clear spray cans from Lowe's. I did all the sanding wet. Just one other thing, the first three coats of black I put on were really heavy, sorta like a primer coat. I could not find any lacquer based primer and spraying lacquer over enamel is not a good thing. If you wanted to try an auto parts store or autobody supply you might be able to find lacquer based primer that woulld fill scratches better than the black paint.

JonP

10-21-2006, 07:40 PM

Thanks Thomas,

I am starting a new thread with some other questions.
I found this article where multiple layers of felt appears to make an improvement if it is securly attached to the board. The author does state that sandwiching the felt is a better option.

http://www.audioholics.com/techtips/audioprinciples/loudspeakers/MechanicalNoiseLoudspeaker.php

http://www.audioholics.com/news/uploads/Figure8.jpg

Looks like I need to research this issue a little more.

Not sure if you really started another thread and it's copied here, or just changed the title, but I'll look later...

I've played a bit with classic #30 roofing felt (the thicker "tar paper" to most of you) as a dampening materiel and it does work with enough of it. I didn't try a constrained layer, just stapled layers on the inisde. I also only have the "calibrated knuckle" for testing. The boxes were moderatly large (1.2 cuFt) of moderately thin (5/8" BB) stuff, pretty ringy. It seemed help a fair amount, but you need >3-4 layers to do a good job.

The stuff is very cheap, it costs $15 a roll, but you have a LOT of yardage on the roll, several speaker cabs worth. Downside is it's hard to work with, a bit messy and hard to cut... and you're doing a lot of cutting for 4+ layers of 6 sides of the box! That's the main reason I didn't try 5 or 6...

Another note, I did not glue, just stapled in with a heavy stapler. I seemed to notice it damped better if all the layers were not heavily stapled.. just tacked every 2-3 inches. Perhaps this gives better LF damping if the damping stack is kind of "fluffy". I know this contridicts the article's findings, but it's a different case with unglued layers It might not dampen HF as well as a solid laminated layer or you need may need more thickness if it's more solid.

Would be good for one of the accelerometer guys to investigate...

technimac

10-22-2006, 02:54 AM

I finally finished my center channel!! ... And if anyone has suggestion for getting a good picture of a gloss black baffle with artificial light I'd like to hear them.
Jim
Jim,
That's a beatiful WMTW center you've done. I have an affinity for the black baffle/oak sides and top look. :W I'm sure you'll be pleased with how it sounds.

It's hard to photograph details with a black on black surface. And gloss black is the hardest :banghead:

I tried using diffused indirect (natural) light and varying the camera angles to the baffle.
The result is here: http://www.avsforum.com/avs-vb/showthread.php?p=8611062&&#post8611062

Note that the baffles on the MTM's and WMTW center are exactly the same color and finish (clear satin over flat black), but the greater amount of reflected light from the MTM's makes them appear "grayish". :huh:

The WMTW center is what all of these look like in most lighting conditions.

Photoshop is your friend. :W

Cheers, Bruce

Brian Bunge

10-22-2006, 10:15 AM

Jim,

That looks awesome! In what part of Central Florida do you live? My fiancee and I lived in Oviedo before she got transfered to Palm Bay. I sure could use some help on some gloss black painting for my sub and surrounds when I get around to building them.

BigJim_inFLA

10-22-2006, 11:30 AM

technimac,

Those are some nice looking speakers! I like the satin over black. I was thinking natural light would be better for taking pictures of the black, but I don't get much light in my apartment, its surrounded by trees. Maybe I'll have to take it outside.

Brian Bunge,

I'm in Altamonte Springs. I'll gladly help if I can get a listen to your MTMWW's. I was thinking about building a pair of those for myself.

Brian Bunge

10-22-2006, 11:47 AM

Jim,

You're welcome to come down any time! The towers and center have gloss black on the fronts and back and I really want to do the same on the sub and surrounds. I just have to get around to building them! :(

Badgas

10-23-2006, 03:46 PM

Hi everyone,
I’m new to DIY speaker building. I am considering building the DM Seas sealed TMWW towers and Seas WTMW center channel. It seems that everyone that has built these speakers is very pleased with their sound and the cost is reasonable. I have a few questions: 1. Is the DM Seas center channel crossover schematic finished. I down loaded a schematic for this speaker using the seas tweeter but I’m not sure if that was the final design. 2. There are a great many sound damping materials on the market. Because these speakers are sealed should the entire speaker be filled with damping material, if so what kind? Should I use only one kind of damping material or is a combination better? 3. None of the cabinet drawings I’ve downloaded so far have any access door in the speaker. Does that mean the crossover is sealed in the speaker forever? I’m assuming no damping material should touch and/or cover the crossover? 4. I would like to radius all corners on the speakers. Is it possible to veneer compound corners? If it isn’t I will consider a spray on surface texture and paint. Thanks for your help.

MrMike

dynamowhum

10-23-2006, 04:16 PM

Welcome to the big show. 1. On the access door you can design your own or make your cross over boards small to go through your woofer holes. 2. On the center channel I wrapped all the vertical walls in egg crate foam and it seemed to work for me. Experts can tell you better. I haven't had time to test my stuff yet. 3.I don't know about the seas as I went with the dayton. 4. Radiusing all edges is tough to veneer. If you had access to a vacuum press you might attempt it, otherwise I wouldn't. Cheers

Badgas

10-23-2006, 05:04 PM

Thanks for the info. I recently saw a set of tower speakers that were painted on the end pieces and veneered through the center. They were very nice and looked doable. In that configuration it would be possible to have radiused edges everywhere and veneer as well.

So even though the speaker is sealed you did not use damping material everywhere. Is there another thread or web site that might speak about sound damping speakers? I have already considered where and how to create an access door if the crossover is too large to fit through a woofer hole.

I heard the Seas tweeter brightened the sound up just a little bit over the Dayton tweeter. Both have had great reviews.

MrMike

dynamowhum

10-23-2006, 07:56 PM

I don't know about a website, I was pretty much told put some in and see what happens. They will tell you on this site that good sound is a subjective thing after a point. The seas is a more inexpensive option and many here like it better than the dayton. I went with the dayton because I could order everything from one place. My hearing isn't what it used to be so either choice is fine. It is easy to veneer 2 edges on a panel it is something else to do 4. It is of course your option. Please make sure to post pics of your stuff as it is all about sharing information on this site. Cheers

Badgas

10-24-2006, 02:40 PM

Yes, I will post picturs. Thanks for the info. I'm puting together my order list today. I have a friend that owns a cabinet shop. He can cut all material on a CNC controled router. All I have to do after that in glue and scew. That does bring up one question. I'm going to glue and screw the panels of the speaker cabinet together. If I countersink the screws and then leave them in place, will this have any adverse effects on the cabinet over time. Will screws vibrate loose?

Dennis H

10-24-2006, 04:32 PM

You can leave the screws in for extra strength unless you want to round the edges with a router. Then you'll need to pull the ones the router might hit. Either way, you'll need to fill the screw holes. Your friend with the cabinet shop can tell you what kind of filler to use.

Badgas

10-26-2006, 08:15 PM

Thanks for standing in, Igor. I was detained by a band of unruly citizens with torches. Don't sweat the dcr on the big woofer coil. A steel laminate is fine. It's not critical. I just put in a rough approximation. I should have used the same value as for the RS version. Resistance variations are much more critical in the shunt circuits. The resistors that represent dcr, and aren't real, are 1011, 1031, and 2051. Also, after rechecking some measurements, you can eliminate inductor 2021 in the mid circuit. All you need is the 40 ohm resistor. The coil doesn't pass a cost-benefit test. Sorry Chuck--could you make that change? Thanks!

If I I'm reading the correct Xover design, there isn't a inductor 2021. I am looking at the "Official" DM WMTW Center Seas Xover design from a few posts back. In this design the mid range circuit only has two inductors L2061 and L2051. I am not sure where the 40 ohm resistor goes. Does this resistor replace an inductor or is it in series with an inductor? Also I would like to use the shielded versions of the RS Dayton speakers. I'm assuming this center xo is opptimized for those speakers? Thanks

chasw98

10-27-2006, 07:33 AM

If I I'm reading the correct Xover design, there isn't a inductor 2021. I am looking at the "Official" DM WMTW Center Seas Xover design from a few posts back. In this design the mid range circuit only has two inductors L2061 and L2051. I am not sure where the 40 ohm resistor goes. Does this resistor replace an inductor or is it in series with an inductor? Also I would like to use the shielded versions of the RS Dayton speakers. I'm assuming this center xo is opptimized for those speakers? Thanks

Here is a link to the Dennis Murphy Seas crossover WMTW center channel crossover schematic (http://www.htguide.com/forum/showpost.php4?p=289904&postcount=1388).
There are only 2 inductors in the mid circuit. Correct, there is no inductor L2021 (Dennis had played with putting one in there but took it out when it cost more than what it did for the XO.) The 40 ohm resistor is R2021. It does not replace an inductor nor is it in series with an inductor. PM me if you need some more clarification.

Chuck

Badgas

10-27-2006, 02:50 PM

Yes this is the Xover schematic that I was referring too. I did not realize DM was talking about a hypothetical inductor. I will build the Xovers to this design. Thanks for the clarification.

chasw98

10-27-2006, 03:03 PM

Yes this is the Xover schematic that I was referring too. I did not realize DM was talking about a hypothetical inductor. I will build the Xovers to this design. Thanks for the clarification.

Well, for about 20 minutes it wasn't hypothetical. I posted a version with the inductor. Dennis alerted me and in the interest of avoiding confusion reloaded the proper approved schematic. Sorry to cause any concern. Ahh, the fun of DIY.

Chuck

Badgas

10-27-2006, 05:34 PM

I didn't see the 20 minute version. I have spent quite a bit of time just trying to get my facts straight about which version of these speakers I wouls like to build. There are a lot of posts in this thread, many of which could be or have become theads of their own. There is a summerized version of this thread, even it is not always accurate or complete. But all of that is to be expected when so many are interested in a particular subject. The benifits of all this information and hard work by so many is that the average person doesn't have to be a audio engineer to build a great set of speakers. With that said I'm pretty sure I have all the info I need to order parts and start building cabinets. I'm looking forward to the project and eventually great sounding speakers.

But of course I do have one question. I have been uneasy about the placement of the crossovers inside the cabinet. From an accessibility point of view the back of the cabinet seens like the most appropriate location to mount Xovers. However from a sound wave damping point of view I would like to place sound damping material there. I don't think covering the Xovers with sound damping material is a good idea or is it? Any ideas?

Thanks
MrMike

chasw98

10-27-2006, 05:41 PM

But of course I do have one question. I have been uneasy about the placement of the crossovers inside the cabinet. From an accessibility point of view the back of the cabinet seens like the most appropriate location to mount Xovers. However from a sound wave damping point of view I would like to place sound damping material there. I don't think covering the Xovers with sound damping material is a good idea or is it? Any ideas?

Thanks
MrMike

My solution:
http://i21.photobucket.com/albums/b297/chasw98/RS3ways/DSCN3765.jpg

http://i21.photobucket.com/albums/b297/chasw98/RS3ways/DSCN3767.jpg

Badgas

10-27-2006, 08:05 PM

I like it! Access panel here I come. Thank you.

ibilisi

10-29-2006, 04:54 PM

For those of you that are doing or have done the black front baffle with the veneered sides, what what your method of construction (after the box was all cut and glued except for the front baffle)?

A. Glue the front baffle, paint, tape the front baffle, then veneer the sides
B. Glue the front baffle, veneer the sides, tape the sides, paint the front baffle.
C. Paint the front baffle, Veneer the sides, Glue the front baffle.

Any thoughts?

spmachina77

10-29-2006, 05:46 PM

....i went back and found my answer in the thread.....

BigJim_inFLA......i love how the screw match the veneer you used

BigJim_inFLA

10-29-2006, 06:40 PM

For those of you that are doing or have done the black front baffle with the veneered sides, what what your method of construction (after the box was all cut and glued except for the front baffle)?

I glued the front baffle, veneered and finished the sides, then masked off the veneer to paint and sand and polish the baffle. It is quite a bit of work because of how heavy this center is. I have to carry the speaker outside to paint it, then back inside to sand and polish. When doing piano black that requires quite a few trips in and out. When I do the mains I will be painting the baffle before I glue it just so its easier to move around while painting and sanding.

spmachina77

10-29-2006, 08:11 PM

just referring to these 2 pictures.
In the center, it appears that the tweeter and mid are completely sealed off in there own eclosure, and the rest of the enclosure is shared by the 8's

However, in the towers, at least this picture i'm seeing, it looks like the mid has its own enclosure, but the tweeter is actually with the woofers. Is this correct?

http://i21.photobucket.com/albums/b297/chasw98/center%20channel/DSCN3725.jpg
http://www.htguide.com/forum/attachment.php4?attachmentid=6162

addition: I did a little more reading and there is a few tower designs out there.
http://www.cyberfrogs.net/files/3way%20tower%20dennis%20murphy%20sealed.png

so the tweeter doesnt' really have to be in the enclosure with the mid, as long as the mid enclosure is the same size.

Also, fire wiring the mid and twetter, would you just drill a small hole and run the wires through (then seal with silicone)? Thats what i've done the the past....any better way to do it?

BigJim_inFLA

10-29-2006, 08:37 PM

That is correct. There are a few different designs for the towers, one of which has the tweeter and mid in the same enclosure similar to the center channel design, and one that has just the mid in its own enclosure. The internal volume of the small enclosure is the same in both, 5L, but I believe the mid only enclosure is deeper to better dampen reflections from the back of the driver. Either way works, though.

spmachina77

10-31-2006, 02:55 AM

can somebody help me, I'm ordering parts to do DM's seas wmtw center channel

I'm a little concerned about the tweeter being a little bright for my taste

I know you can change the crossover to attentuate or "pad" the tweeter output (i just don't know how to do it)
the crossover I see here includes 3 resistors
r3021 -8ohms <edit>
r3031 -3ohms
r3041 -12ohms
http://i21.photobucket.com/albums/b297/chasw98/Chuck%20CC/sc_0002.gif

can somebody explain to me how I go about changing the resistors to pad down the tweeter (and of course which ones I need to change)

I just want to order the extra parts so I can try it both ways to see what i like

thanks

Dennis Murphy

10-31-2006, 11:05 AM

There are 3 approaches you can take. One is to increase the 3 ohm resistor to 4 ohms. Another is to reduce the 12 ohm resistor to 10 ohms. The third is to do both. The first will tilt the top end down a little. The second will shelve down the entire tweeter response. And, of course, the third will do both and will have the most impact. So I would order a couple of 4 ohm and 10 ohm resistors and experiment.

spmachina77

10-31-2006, 02:25 PM

thanks dennis, that helps tons,
I do have one other question, i noticed that compared to a few pages back (when it was first posted here) post #1388, r3021 has changed from 8 ohms to 10 ohms.

you explained how the other 2 resistor effect the crossover, does this resistor also come into play with brightness as well?

and just to make sure, reffering to the actual seas tmww towers, cause i'm doing them next, does this same rule apply??

r3021 10ohms
r3061 3ohms (higher reistance, ie 4ohms, shelves down the upper end of the tweeter)
r3071 10ohms (lowering this to say 8 ohms, shelves down the entire tweeter)

Dennis Murphy

11-01-2006, 02:55 PM

[QUOTE=spmachina77]thanks dennis, that helps tons,
I do have one other question, i noticed that compared to a few pages back (when it was first posted here) post #1388, r3021 has changed from 8 ohms to 10 ohms.

Hi Now I'm getting cornfused again. Post 1388 refers to the towers, not the center channel. They don't have the same exact crossovers. In any event, a resistor in front of an inductor that is wired to ground ("shunt circuit") controls the shape of the roll-off at the low end of the tweeter response. It doesn't really affect the response higher up. The value is usually critical, and you can't make even small changes without degrading the phase coherence and frequency response around the crossover region. You change the high frequency response by adjusting the "L-Pad," which is the final series and parallel resistors in the tweeter circuit. Some people are confused when I suggest lowering the value of the parallel resistor in order to decrease the overall tweeter level, since you usually think of higher resistor values as lowering tweeter output (which is true for a series tweeter). But the logic is clearer if you visualize lower and lower values, until you place a straight piece of wire (0 ohm resistor) between the positive and negative tweeter terminals. That will completely short out the tweeter, resulting in no output. The higher the value of the resistor, the farther you move from a short.

spmachina77

11-01-2006, 04:02 PM

hey sorry dennis....my bad for confusing you

I don't know where I saw that change....read this entire post within a couple of days so i'm a little overwhelmed.

Anyways, I do understand how the l-pading works now

i'm ordering all the parts for the towers and center channel (won't have the towers done though for a few months.
I'm going to use the schematics below....if any of them have been updated, please let me know

post #1388 schematic for the wmtw, using seas tweeter

post #257 is for the tmww towers using the seas tweeter

Dennis Murphy

11-01-2006, 04:44 PM

:oops: post #1388 schematic for the wmtw, using seas tweeter

post #257 is for the tmww towers using the seas tweeter[/QUOTE]

I think maybe we were both confused. Post 1388 is for the center channel--I misinterpreted the first sentence. But my observation still holds. The resistor for the center channel didn't change from 10 to 8 ohms. It's just that the tower and center channel don't use the same resistor value. And if you compare Net2 for the two designs--they're completely different. That's because the driver locations on the baffle are very different.

spmachina77

11-01-2006, 05:54 PM

yeah, I know they are different.....just ordered parts, can't wait to start work on them...

thanks dennis for the design, and your help with it!

Brian Walter

11-02-2006, 10:02 AM

Dennis,

Since you say the value of the resistor in front of the inductor in the shunt circuit is critical, then I would think so is the DCR of the inductor. For example in the tweeter circuit for the tower, the shunt resistor is 10 ohms and the inductor is 1.2 mh. If you use a 20 GA inductor with a DCR of 0.8 ohms versus a 14 GA inductor with a DCR of 0.24, there is a significant difference in total resistance. Since the inductor is in series with a resistor, I would say there would be little benefit to using a low DCR inductor, so is it safe to say you based the design on using a fairly high DCR inductor at this location? I used an 18 GA inductor with a DCR or 0.60, should I adjust the series resistor so the total resistance is 10 ohms? Do you know what the total DCR was in the version you tweaked?

The reason I'm asking this is that at DIY-Iowa, I thought my speakers lacked a little sparkle compared to a lot of the others, so I removed the additional tweeter padding I had previously added, and now they don't sound right to me. It did put the sparkle back into the highs again though. So I was thinking maybe I need to adjust the series resistance in the shunt circuit.

Brian

Dennis Murphy

11-02-2006, 12:53 PM

I saw quite a few favorable comments on your speaks, so maybe the other entries were a little bright. Anyhow, I generally assume people will use 16 Ga inductors, and set the resistor value to allow for that. Although the value is "critical" in the sense that you don't want to deviate by more than .5-.8 ohms, differences of, say, .2 ohms won't matter. I wouldn't fool with the shunt resistor. It won't add or remove "sparkle." Changes could add an irritating glare in the 2500 Hz range, or cause a slight hole in the upper midrange. But sparkle isn't what that resistor is about.

Brian Walter

11-02-2006, 01:34 PM

Dennis, humor me a minute, would increasing or decreasing the resistor cause the irritating glare in the 2500 Hz range? I'm thinking that might be what I'm hearing when I don't use the additional 1 db of padding. With the additional padding in I don't notice the irritating glare, but the with the stock crossover I hear it. It's too bad I have to remove the midrange to get at my crossovers or I'd play around with some small changes to that resistor.
Brian