Help choosing a design for some towers

[---k---]

You're just using the pink fluffy stuff, right? Your local Lowes, HD will have unfaced. Just ask. Otherwise, if you got some with a face on it, just peel it off. Even if you loose a little bit of it, it isn't that big of a deal.

[bf_brock]

I haven't bought the fiberglass yet but I don't recall seeing any that was unfaced. I think they had R13 and R19. I can't remember what color they were, but I believe it was backed only on one side. HD in my area doesn't seem to have much selection at all. Lowe's had a way better selection. I'll go and look again later this week when I'm ready to start installing it.

[cjd]

I really recommend using the panel fiberglass over the fluffy stuff. Makes any hand-in-box work nicer (and even then... ugh.) But it's even harder to find.

[---k---]

the fiberglass panel stuff CJD is talking about is Owens Corning 703 - the yellow stuff in my photos. You're not going to find it at Lowes, HD, etc. It is usually only available from HVAC contractors and Insulation companies, or mail order. I mail ordered mine, and that gets expensive.

Fiberglass doesn't bother me, but I'm "the last of the tough guys". Just grin and bare it with the Pink stuff. Or, you can always try the cheap egg create foam from Walleyworld. Some say it works, others say it doesn't.

So got any photos yet? When do your drivers and parts arrive?

[bf_brock]

No photos yet. I got all the panels cut on Saturday but had a limited time frame so all focus was on cutting. I'm going to try to get the speaker holes and bracing holes cut after work over the next couple of days. I'll get some photos of the remaining progress.

I'm expecting deliveries today, tomorrow and Wednesday. It'll be like Christmas. :-) The drivers and most of the crossovers parts should be delivered today.

[bf_brock]

I got most of the parts today. I didn't get a whole lot done on the build though. I did manage to get the speaker holes cutout on one board. I'll be able to use that as a template for the others so that'll go quicker. I'm going to try and get the crossovers built during this week and then try to get the rest of the box work done this weekend.

Here's a link to where the photos will be. I've got a couple photos up of the parts and you can see the condition of one of the boxes. Everything looked to be ok though. I'll post more photos as I get some of the build done. Nothing exciting to photograph yet.

Build Photos

[---k---]

Just make sure you reverse the mids and tweeter offsets on the second baffle.

[bf_brock]

I got it. I've been checking, rechecking, and then just for good measure checking again with everything I've been doing and made sure to flip the offsets for the second baffle. I did manage to break part of my Jasper Jig. I was able to continue using it but the pivot pin was barely hanging on. The base is made of acrylic and I found it doesn't take much of an impact.

[JonP]

How deep do I need to route the recesses for driver flush mounts? I haven't received my drivers yet so I can't just measure them.

Here's a tip.... resist the tempation! Wait till you have the drivers in front of you, then do a scrap piece test of your measurment/router setting. Kind of hard to go back from if you screw it up...

Buying a cheap digital caliper (Harbor Freight) is a good thing for measurements like this... accurate and handy for loads of other measuring tasks.

(oops.. looks like I'm behind the curve a bit...)

[bf_brock]

Thanks JonP. I did receive my drivers so no need to guess. I actually did hold off on the temptation.

[cjd]

I use the driver flange to set the depth stop in my router (with the plunge set to have the bit flush with the router base at the time I set the stop). Just put the driver flange against the stop on the base, and adjust the adjustable part down to meet it. perfect (or nearly) every time.

[Ray Collins]

Chris,
I use the same technique but add a little to accommodate the gasket.

Ray

[bf_brock]

I updated my build photos. I'm a little further ahead than the photos show. It's coming along ok, only a few snags or so. I did manage to get several deep scratches on the side of one of the speakers. They're too deep to sand out but I should be able to reduce them.

Considering my complete lack of experience I think they're turning out pretty well. I will say that this has been quite an undertaking so far. It probably wasn't the best project to learn on. :-)

Build Photos

[---k---]

Looking good. I see you're the type to round over your braces. :T

In my mid chamber at mid height along the sides, I stuck a 1" wide x 6" piece of 3/4" ply. It braces the side a bit of the mid chamber, but more importantly gave me something to secure my tweeter crossover to. If you drill a couple holes in it, you can zip tie it down, but I'm just using velcro. Before you put the front baffle on, think about what you're going to secure the mids and woofer crossover too.

The insulation looks good. Make it thicker on the back wall behind the drivers.

To get the scratches out, you might want to try using an Iron w/ a damp towel. The water and steam will raise the grain some and can raise the scratch. Then, when you sand it, its all gone. It works. You just got to be careful not to get carried away to much.

[bf_brock]

Actually I'm planning on handling the where and how of securing the crossovers and running the wire inside in the cabinet today. I was planning on putting the tweeter crossover in the woofer cabinet along with the other crossovers. As far as my estimates go I should have room to install it there. Otherwise your idea would be doable too. I already have strips of the ply I could use for that.

I actually used a thicker insulation on the rear. I think it was the 3" thick stuff. I didn't get a photos of it before the back panel was installed because my camera battery died and I wasn't going to wait for it to charge before installing the panels.

Thanks for the tip on getting the scratches out. I talked to my dad about the scratches and he recommended the same thing.

I'm close to completing the build. I've got to run the wires, do the crossovers and install the front panels. Oh, and screw the feet in. Do you recommend doing a felt treatment or something to the backside of the front panel for dampening? After that it'll just be the fun process of sanding, staining and doing a few cosmetic repairs here and there.

[---k---]

Put the tweeter crossover where ever it fits best.

You're insulation sounds good so far. I would definitely put some on the back of the baffle down low, where there is empty space. I don't think I put any around the drivers - there just isn't room for any. If you can get some in there, without obstructing the back of the drivers, can't hurt - only help.

And, you're going to build the base up or something along with the spikes, so you get ~3" under the port between the floor and the port - right? I know we talked about this at one point.

Staining and sanding takes the longest of all! Mine still aren't finished like I want them. This spring, I'll be tearing them apart and doing a better job with the paint. Ughhhhh.

[bf_brock]

And, you're going to build the base up or something along with the spikes, so you get ~3" under the port between the floor and the port - right? I know we talked about this at one point.

This is exactly what I'm doing. I think it'll end up a little under 3" but I think I can live with it.

I've got a few areas left to put insulation that I spaced out when insulating initially.

[bf_brock]

Some clarification on the crossovers:

The tweeter is hooked up normal, positive speaker to positive crossover and negative speaker to negative crossover.

The mids are hooked up in series, one speaker neg. to the other pos. Then one speakers neg is hooked to the neg. on crossover and the other speakers pos. hooked to pos. on the cross.

The woofers are hooked in parallel. pos. speaker to pos. speaker and neg. speaker to neg. speaker. Then they are hooked up as pos. speaker to neg. cross and neg. speaker to pos. cross. Now I'm only guessing on the part of reversing the connections at the crossover because you have them marked with a minus sign on the crossover diagram.

So correct the mistakes please.

[cjd]

You got it right. Make sure the wires TO the crossovers from the binding posts are + to + and - to - for all crossovers.

Reversing polarity of hook-up is a 180 degree phase shift. The woofer to mid connection needs this. The mid to tweeter does not.

You could also wire woofers "right" and the mid and tweet both "backwards"

C

[bf_brock]

Thanks for verifying that cjd. I did the initial layout of the crossover components last night and should have them soldered up today.

[---k---]

Mine still arn't soldered. Just twisted together.

Did it that way for testing. Will solder when I take them apart to do the final painting.

[bf_brock]

How are you guys connecting the wire to the speaker leads? Solder, crimp-on connectors?

[cjd]

Yes.

I've used both.

C

[bf_brock]

Yes.

I've used both.

C

Is one method preferred over the other? :

[Concillian]

Is one method preferred over the other? :

Yes. Whichever method you prefer is the preferred method. :P

[---k---]

Use the crimp on connectors. It will make taking the drivers in and out easier.

[bf_brock]

Crimp-on it is. That's much more convenient.

[Geoff Gunnell]

It's harder than it used to be to find the non-insulated crimp-on disconnects locally -- I usually cut the insulating plasic off (easiest way I've found is to hold the disconnect by sliding it onto a tapered awl) -- then I can crimp and solder the disconnect to the wire.

[bf_brock]

It's harder than it used to be to find the non-insulated crimp-on disconnects locally -- I usually cut the insulating plasic off (easiest way I've found is to hold the disconnect by sliding it onto a tapered awl) -- then I can crimp and solder the disconnect to the wire.

That's actually a good idea. I may do that.

[bf_brock]

I'm semi-completed! The Khan's are up and running since late last night. Pretty much everything went wrong yesterday. I was just a bad day. I don't feel like rehashing it all but it was just everything, not just the speakers that went wrong yesterday. Anyways, right now the crossovers are external and I had issues with a couple of the speaker spike screws so I didn't any of the feet. They're just sitting on some little pieces of scrap I had left over. So besides those two speaker issues I think they turned out well. Considering my lack of woodworking skills and knowledge I think they turned out as well as I could have imagined. I did learn a lot and I think if I do another project it'll probably turn out even better. I think I may leave the crossovers external and build a box to put them in.

Another note. I would not recommend the Lowe's "Professional, Cabinet Grade" birch plywood. It's expensive and it's crap. The outer finish is nice but it has way too many internal voids. I ended up having to do quite a few patch jobs to fill the voids. There wasn't any way to avoid it.

So how do they sound. Great! Yes, even my rock albums sound good. :-) They have a level of clarity that I don't think I've heard before. Last night I played a couple of The Mars Volta albums; including my favorite album Frances the Mute on vinyl. I've never heard their albums so sound so good. Today I played some Norah Jones live DTS audio disc that some gave me a long time ago. Man it sounded good even if it's not your type of music. I've also played some various MP3's and they sound good too. So far they've done well with everything I've thrown at them.

I'm glad though that I choose to go with this tweeter. It's not laid back at all and I think that it's very clear. The speakers as a whole are very neutral and revealing. At first I thought it was going to take a while to get used to compared to what I previously owned, but I guess not. I'm already used to it. I can definitely give my recommendation to anyone thinking about building these. Ryan, you can be at ease now. You and CJD created a very nice speaker.

There are some updated photos posted. Oh, and the speaker holes are actually round unlike they appear in the photos. I did the photos on our laptop and the photo program I have loaded on it doesn't do a very good job with resizing circles when I shrink the photos.

Build Photos

[dawg1161]

Looking good, Nice build thread.

[cjd]

You have a crappy day that ends in good sound?

Now that's what I call progress!

Enjoy!

[bf_brock]

You have a crappy day that ends in good sound?

Now that's what I call progress!

Enjoy!

Thanks cjd! I will enjoy thanks to your design. Now I have to save up the "do whatever I want" funds to build the center channel. I'm really happy with the finish I chose to do and it was very easy to do. I ended up leaving the ply bare and then staining it. I think it turned out well.

[---k---]

Ahhh, I still don't have spikes on mine either!

I understand about bad days. I've chronicled many.

I'm glad you like them. Iowa was a good gut check that these are as good as I think, but there will always be a part of me that doesn't think that something I built is this good. Ya know?

I find it interesting that you haven't found anything that sounds bad on them. I feel the same way. I always hear people complain about poor recordings, but I don't really get that with the Khans.

Post some more thoughts after you've had a few days with them. I'm particularly interested in the bass. Maybe plug your port and hear the difference, or lack there of. I'll cut and paste your recommendation for ported into the original build thread to give others the option.

Also, good pictures of your crossover would be great. You got the updated crossover, and that is yet another thing on my list of things to finish with these.

But, the center is awesome also. When you going to start on it?

[---k---]

Also, that doesn't look like an approved roundover on the edge! :B

[bf_brock]

Also, that doesn't look like an approved roundover on the edge! :B

It's 3/4" instead of 1". Close enough. :-)

[bf_brock]

Ahhh, I still don't have spikes on mine either!

I understand about bad days. I've chronicled many.

I'm glad you like them. Iowa was a good gut check that these are as good as I think, but there will always be a part of me that doesn't think that something I built is this good. Ya know?

I find it interesting that you haven't found anything that sounds bad on them. I feel the same way. I always hear people complain about poor recordings, but I don't really get that with the Khans.

Post some more thoughts after you've had a few days with them. I'm particularly interested in the bass. Maybe plug your port and hear the difference, or lack there of. I'll cut and paste your recommendation for ported into the original build thread to give others the option.

Also, good pictures of your crossover would be great. You got the updated crossover, and that is yet another thing on my list of things to finish with these.

But, the center is awesome also. When you going to start on it?

So far the bass is good. I guess I'm a bass head though because I want more. The bass is tight, accurate and detailed. I'll report more on it after a few days of listening but so far, so good.

I had some worried thoughts in the back of my mind about the build. Not only from my lack of experience building, well anything, but also the fact I'm building a design made by someone on the Internet that I don't know and a design that I haven't heard. But I trusted what people have said who heard the design and went for it. And it turned out well. So now I can back you up when you recommend the design to others.

[bf_brock]

Ahhh, I still don't have spikes on mine either!

Also, good pictures of your crossover would be great. You got the updated crossover, and that is yet another thing on my list of things to finish with these.

You posted photos of the updated crossover but didn't install them?

[---k---]

Nope. Right now, I got a list that consists of: updating the crossover, soldering the crossover, finishing the paint, and putting some type of spikes on them.

With all the bantering we do around here, I just never seem to find the time.

[bf_brock]

Well yesterday I decided to run the auto calibration on my receiver. I have the Yamaha RX-V1500 by the way. Previous listening to the speakers was with the auto calibration set with my S38's in place and equalizer setting on Low (that is supposed to calibrate all speakers with an emphasis on lower frequency accuracy). This seemed to work well with that setup and frankly the Khan's sounded great even though it wasn't configured with them in place.

So I decided to re-run the auto setup and set the equalizer settings to Front (recommended when your main front channels are better quality than the rest) which is supposed to leave the FL/FR channels alone and calibrate the other speakers to more closely match the front channels. First problem was that it kept saying the wiring was incorrect and that the front channels were out of phase. At the time I didn't think about the fact that the woofers are wired out of phase. That would cause it to falsely give an error, correct?

So I started investigating the wiring. Turns out I had a couple of wiring connection errors. On the left channel I had the output for the midrange wired in reverse and on the right channel I had the wiring coming from the receiver into the crossover wired in reverse. I corrected both of those. I didn't notice any difference with the right channel after I corrected the wiring but I did notice a difference with the left channel. I had thought that the right channel seemed to sound a little better than the left. Turns out I was right and it was because the midrange of the left channel was wired out of phase. That also brings up another point in that even when the midrange was wired wrong it still sounded good.

Anyways, the receiver still says the front channels are wired incorrectly and out of phase but I have now triple checked the wiring and everything looks correct. I re-ran the auto setup again. The unusual thing is that it set all speakers to small and crossover to 200 Hz; even though all the speakers clearly reproduce freq. well below that. I changed the Khan's to Large and set the crossover frequency to 60Hz I think. Last night after I ran the auto setup I listened to one CD and watched a couple of HD TV shows. I think that my center channel (JBL S-Center) sounds better now after having the auto setup equalize to the FL/FR and it blends better. I have to do some more 2-channel listening with the Khan's now that I re-ran the setup.

[---k---]

Glad to hear that I'm not the only one that wires things up wrong the first time.

I read several complaints about receivers saying that speakers are out of phase when they aren't. I seem to even remember reading this in a Secrete's review. However, my Pioneer 1015tx gets the Khans right. Can't comment on the Yamaha.

Because you say that it is setting the crossover to 200hz, I'm thinking something is amiss.

The woofers being wired out of phase wouldn't cause the receiver to report out of phase. Out of phase would indicate that the left is out of phase with the right. Maybe just from the receiver to the binding posts, maybe somewhere internal. I'm really concerned about it choosing a 200hz crossover. You might want to get a test disc, like Avia, that has some frequency tones on it. Play the tones and see if there is something amiss. There is also the free NHT frequency generator program if you can plug your computer into it (see Mission Accomplished for the link).

Avia also has in-phase and out-of-phase tones you can use to check your receiver. I've done this before with the Khans, and it is obvious when they are in-phase versus out.

I know they sounded great to me when I had my woofers wire backwards, but something just wasn't right. It was hard to put my finger on, because it is such a narrow band that is affected. But, they sounded so much better when wired correctly. It is worth tracking down.

[cjd]

Yeah, flip the wiring to the mains, it *should* tell you're they're correct after that.

With the mid wired backwards, you'd have a suckout on both ends of the driver's range, resulting in lackluster bass and a lot of lacking presence.

C

[bf_brock]

I'll check all the wiring again just to make sure. Based on my use they are clearly playing below 200 Hz as they do not seem lacking in bass at all. If something is wired wrong it would have to be at the speaker connection as I verified everything else. If I can't find anything wrong I'll run some test tones. I have the Sound and Vision test disc, I think it has a phase check on that disc too.

[bf_brock]

Yeah, flip the wiring to the mains, it *should* tell you're they're correct after that.

With the mid wired backwards, you'd have a suckout on both ends of the driver's range, resulting in lackluster bass and a lot of lacking presence.

C

So if I swap the wiring to the mains (even though I know that part is right) and it tells me it's right I should be able to hear a difference, correct? What if it's worst after that? At that point I should probably just ignore it?

[Dennis H]

I've wondered how the receivers detect phase. I'm guessing it's whether the first spike of the impulse response points up or down. But that's just telling you the phase of the tweeter and what really matters most is having all the woofers in phase because bass will be correlated between speakers several feet apart while treble won't. So, you might have a 3-way center with 2-way mains and the woofers could be in phase while the tweeters aren't because of more phase wrap in the 3-way crossover. In that case, I'm guessing the receiver would get it wrong.

One of the best ways to check it is to put two speakers facing each other a few inches apart and play a mono signal through them. Reverse the wires back and forth and the correct wiring will clearly have more bass, no mistaking it.