My first build! Zaph's ZDT3.5 worklog

[tylerdurden]

My parts from PE arrived today. I wanted to start my own thread cuz I may need some advice along the way and I dont want to crap on someone else's thread with questions.
I have alot of experience building cabinets as that is what I have done for a living for years. I also build furniture for fun. I have a fully equiped shop with just about everything. What I dont have is a planer.
I will post pictures as things progress. I am going to use BB plywood for the cab but I want to use some nice walnut, maybe oak, for the baffle and base.
Wich brings me to my first question. The walnut and oak that I may use for the baffle will be in one peice width of 9" as per the design spec. But it is also 1" thick not 3/4". Can I use a 1" thick peice? I know I asked this on another thread but I wanted to ask it here as well. I just want to make sure I dont throw off any of the tuning by moving the drivers forward, or out, a 1/4 of an inch.
I will be rounding over the edges with a 3/4 RO bit and will chamfer the inside of the driver opening as well. Thank you!
Bobby

[Homebrew]

Keep your internal dimentions the same as the plans and the baffle can be any thickness. Mine will be 1 1/4 inch thick solid oak with a 3/4 inch peice of MDF on the inside. Inside dimentions are critical. thick baffles are good.

[Rolex]

Post some pictures along the way. It's interesting to me that you build cabinets for a living, build furniture for fun, but don't have a planer??

[stangbat]

I may be putting the cart in front of the horse but with you being a cabinet maker and furniture builder, I'll be interested in what you do for finishing them. Blktre and I have both ran into problems with our finishes. I've got mine to where they look good enough that I'm not complaining. Blktre is working on getting his fixed and hopefully he is going to be happy with the end result.

Anyway, I'm not trying to crap on or hijack you thread. Just curious of your plans.

[Blktre]

Agree w/Stangbat. Everything is pretty until you start the poly or whatever finish you choose to go with. I think that the iron on method of the veneer raises some of the grain. So you need to put on more than one coat of finish before you sand. Otherwise, you run the chance of knocking down some stain when sanding after one coat of poly. I'm no finish guy, but that is what happened to me. If i would of waited to sand after my 2nd coat of poly then this wouldn't of happened to me. So, im not sure about your finishing experience, but that is something i ran into.

Id like to see your pics as time goes along as well!

[tylerdurden]

HA HA Good question!! My planer craped out on me a couple of months back. I was going to rebuild the motor but the old bitch and I never got along anyways. Id been tryin to kill her for a few years now. It was a hand-me-down from a guy I used to work for, many moons ago. He got it from a sale that the local high school had when they decided to drop woodshop from its class's. Grizzly is having a tent sale at the end of the month up in Bellingham WA. Im going to get a new one and possibly a bigger bandsaw with a larger resaw capability. I will be able to make my own veneer up to 10" wide.

No problem stang!! I am building the cabs out of BB plywood but havnt realy decided on a finish yet. I would like to do a piano black finish but I have never done it on BB. Mdf Is much better for getting that realy smooth finish. The laquer goes on much smoother. Laquer is a pain in the but to get right. At least it is for me.
I dont like covering my furniture with laquers or varathanes, poly's, etc. I like to just use a nice oil finish and leave it alone. Sanding alot and oil will give a nice shiny durable finish IMO. And if you scratch it you can just rub it out with a fine grit SP and more oil. I like the natural finish's.
I went back and looked at yours on AK. Whats wrong with them? Looks damn good to me. What exactly is going on with Blktre's? What type of finish? I will help in anyway I can!!

[tylerdurden]

Yeah I try to give each coat at least 36 hrs to rest. How thick was your veneer. Iv never used Iron on. I glue and press all of mine.

I will post pics to.

[tylerdurden]

I have some plans for the cabs to give them a very unique look. But I want to save it as a suprise . I will give you a hint. It envolves alot of scrollsaw work. :W

[tylerdurden]

One more question. Did you sand the veneer before you started with the poly? or actually before you stained?
I recomend spraying poly if you have the tools but any way you slice it poly is hard to work with. I have never done it but a know people who have got good results using poly in a spray can. Thining poly is the key I think. With spray cans its already thined and will dry faster.
The most important part is preping the surface before you start with the stain. Depending on the wood, I start with a ruff grit working my way down to finer grits. then I finish it off with 0000 steel wool. first coat of stain then more steelwool to take down any spots that lifted. then wipe with tac clothe, stain again and repeat. Always use the wool and tac before you poly. If your brushing the poly on you still may want to thin it a little.
Obviuosly if using a veneer you must becarefull not to sand to heavy but you MUST sand some. I think a common mistake is not preping veneer just as you would any other wood. Just becarefull.

[stangbat]

No problem stang!! I am building the cabs out of BB plywood but havnt realy decided on a finish yet. I would like to do a piano black finish but I have never done it on BB. Mdf Is much better for getting that realy smooth finish. The laquer goes on much smoother. Laquer is a pain in the but to get right. At least it is for me.
I dont like covering my furniture with laquers or varathanes, poly's, etc. I like to just use a nice oil finish and leave it alone. Sanding alot and oil will give a nice shiny durable finish IMO. And if you scratch it you can just rub it out with a fine grit SP and more oil. I like the natural finish's.
I went back and looked at yours on AK. Whats wrong with them? Looks damn good to me. What exactly is going on with Blktre's? What type of finish? I will help in anyway I can!!

Sorry I turned this into a finishing thread for the moment.

Next time I'll probably try an oil finish. Mine look pretty good now. I used Deft Brushing Lacquer. I have used it on furniture in the past with very good results. And my in-laws used it exclusively on a lot of antique furniture they refinished and it looks very, very nice. However, with my speakers I had bad runs. I had to sand and reapply several times. I think my problems were due to me using old lacquer and the wrong type of brush. Once I got a new can of Deft and a better brush, things went much better.

I'm afraid I mislead Blktre with his finish. I had such a hard time with mine I suggested he used polyurethane because I had much better luck using it on my fireplace. I also told him you needed to lightly sand between coats. I think he summed up the problem pretty well and that is my best guess as to what happened with his finish.

These are our first builds and we're still learning. I guess you've got to have something go wrong to make it interesting and so you have stories to tell.

Anyway, on to your project. I'm excited to be able to watch your progress.

[Blktre]

tyler,
sounds like you've got alot of know how on finish. It would be nice for you to share your experience w/some of us that don't so much..Thanks for the tips.

Also, Stangbat makes it sound like our projects finish is not up to par. It is, its just we both are perfectionist and nothing is ever perfect. So you know the circus.....

[dawaro]

I have had very good results with the Deft spray lacquer in a can. I prefer it much more so than poly for speakers. Even when using thinned poly it still dries fast.
If you are having problems with the grain raising try wiping the veneer down lightly with mineral spirits. The loose grain will suck it up and stand on its end. You can then take a razor scraper and scrape it off. When I am using veneer I use mineral spirits but on solid wood I usually just use plain water in a spray bottle.

[tylerdurden]

Those are good tips there dawaro. How long do you let the mineral spirits sit before you use the blade?
I never thought of that.
Veneer always looses alittle of its continuity. On the molecular level when you cut wood it naturaly is going to loose density. This is doubly true with thin veneers. That is why its important to prep it before useing the stain and between coats.

Blktre..Being a perfectionist is a curse, at least that is how my wife defines it, I have as well. Wood is finiky, you can have 2 pcs of the same type and use the same stuff on it and its never going to turn out EXACTLY, a perfectionists term, the same.
Im by no meens a finish guy. I think its a matter of experimenting and finding what works for you then stick with it.
For example I just went and bought some Krylon gloss black spray paint and primer. I have some scrap that Im going to experiment on and see if I can get a Piano black type finish on that BB plywood. If it works great if not I will go back to what I know. Ill let you know how it turns out.

[cyberspyder]

I personally think tung oil looks great on BB:


Images not available


It's even better if you can take the time to really rub in the oil, and it also helps to do quite alot of light coats...In the end, you'll get really nice wood depth, especially in sunshine.

Brendan

[chrisn]

I have some plans for the cabs to give them a very unique look. But I want to save it as a suprise . I will give you a hint. It envolves alot of scrollsaw work. :W

inlay's perhaps? I have seen a picture of that done to a speaker once and it looked incredible. I'll try to find it....


Nice user name btw. I looked to see if you had introduction thread so I could post the 10 rules of Fight Club... er, speaker building

edit: found it: http://briangray.net/projectdetail.cfm?ProjectID=26

[tylerdurden]

inlay's perhaps? I have seen a picture of that done to a speaker once and it looked incredible. I'll try to find it....


Nice user name btw. I looked to see if you had introduction thread so I could post the 10 rules of Fight Club... er, speaker building

edit: found it: http://briangray.net/projectdetail.cfm?ProjectID=26

Uh Oh the jig is up. Yea I realy want to do some inlay on these. But Im really itching to get them done. Im working on the xovers now. I think what im going to do is build some cabs for them now using the BB ply. Then down the road I can work on a nice pair incorporating the inlays at my leasure. Inlays are labor intensive but I LOVE doing them. I cant rush them. I got a mixed bag of exotic wood off of epay. It has Purpleheart,koa, Padauk,zebrawood,brazilion rosewood and several others teak and mahogany I beleive. Decent dimensions to.

I will post some pictures of the xovers soon. Once again.. Thank you Stangbat!! Your pictures are proving invaluable. I probably couldnt do it without them.
This thread needs pictures. I just got this digital camera a couple of months ago just so I could post pics on the forums and have yet to realy use it.

[stangbat]

No problem on the crossover pics. If anyone else needs it, I have a pic of the crossovers with PE parts and the wiring diagrammed to each component.

You are building just the towers, right? No center channel?

[tylerdurden]

Im just building the towers for now. I did buy the drivers for a CC since they are on sale. The CC xover will be different right?
Besides Im in to much a hurry to get these towers done. My wife and I are having a big party at the end of the month. I want to get them done by then.
I cant work on them at all this weekend . My uncle fell ill and I have to take care of him. I will be out of town till monday.

Promise I will get some pics up soon. It isnt much of a work log so far.

[Blktre]

Dang, you must have some serious time on your hands to be able to finish these by the end of the month.....good for you.

[tylerdurden]

Dang, you must have some serious time on your hands to be able to finish these by the end of the month.....good for you.

LOL yeah to much time. Just recently retired. Im driving my wife crazy as much as I can so that she will let me do these types of projects.
Its a stretch to get these done by then but ima going to try :T

[clovergover]

i m building these too... some parts are out of stock at PE..guess have to wait..

[Blktre]

Mine are finished and have been listening and dialing speaker placement in for the last 2 weeks. Stangbat has been over a few times getting a sense as well. You will enjoy these speakers.

[tylerdurden]

Sorry guys! The last half of june was crazy bad. My uncle fell ill and I took care of him for a week. Then my wifes Grandpa died so we needed to go to Kansas City for a week. Just got back on saturday.
Good news Blktre! Glad yours are done. Wish I could come over for a listen.

EDIT:OH MAN!!! I just noticed that Stang is in KC. That must meen you are to. Oh well. %!@& :cry:

[stangbat]

Sorry guys! The last half of june was crazy bad. My uncle fell ill and I took care of him for a week. Then my wifes Grandpa died so we needed to go to Kansas City for a week. Just got back on saturday.
Good news Blktre! Glad yours are done. Wish I could come over for a listen.

EDIT:OH MAN!!! I just noticed that Stang is in KC. That must meen you are to. Oh well. %!@& :cry:

Ah man is right! Too bad we didn't hook up. And yes, Blktre is close to KC. But maybe it is for the better that you didn't get to hear mine. You would have been chomping at the bit afterward.

Actually, I don't think I put my location in my profile until this weekend. I thought I had it there but I happened to notice that it wasn't and I updated it. So you probably wouldn't have had any way of knowing where I was before your trip.

[tylerdurden]

Yeah I was in Lee's Summit. Dog Gonnit! Well I just gotta get mine done. Your right I would have been silently pushing my wife out the door. Just kidding. She was real close to her Gramp's.
I ordered a new blade for my table saw. Should be here by the end of the week. I have decided to use MDF. I want to do a piano black finish and BB ply would be to difficult and it would be a waste of BB.
So im going to finish the crossovers. What kind of glue did you use on them? I was thinking of using Hot melt, but I know some people dont recomend it.

[stangbat]

So im going to finish the crossovers. What kind of glue did you use on them? I was thinking of using Hot melt, but I know some people dont recomend it.

I installed everything and then went back with hot melt glue and tacked everything in place. I didn't know some people were against it. I know it isn't the best glue for a lot of situations, but it seemed to work okay for me.

[---k---]

hot glue for me too. big inductors are strapped down with zip ties.

[tylerdurden]

I remember hearing it on other forums. I have used it alot in computer modding with no problems. And yes I will be using Zip ties as well on the big stuff.
Thanks guys
Bobby

[WillyD]

I use hot glue for everything, including the big inductors. Call me crazy, but it works.

[tylerdurden]

Hey guys, What kind and size wire do you use for connecting and the common grounds. For example at L22, the 3.6mh Big Erse inductor's wire isnt long enough to reach the terminal strip, what can I solder/splice on the end of it? Also between C11 (15uf cap) and L13 (2.00mh inductor) on the mid board it shows a wire runing to the terminal strip. What do I use? Also from one board to the next for Positive and negative and to the drivers, what do I use?
I have some 18awg stranded hookup wire in 5 different colors and I also have some speaker wire ranging from 12awg to 18. I almost purchased some 14 and 16awg solid core copper wire but I figured I should ask you guys first. Any advice?
Oh and I also have some old inductors from old speakers lying around. I dont know the value of them so I figured I could use a little of that for the common ground on the strips or some of the thiner wire that is to be unwound from the L1 inductor.
Thank you
Bobby

[stangbat]

Solid core is easiest to use. 16 AWG is fine. I wouldn't sweat using 18 AWG since you are talking about short runs. There is nothing wrong with stranded, it is just more of a PITA to solder.

You may know this, but be aware that any wire from an inductor is going to be varnished and you need to scrape off all the varnish before you solder.

[tylerdurden]

Solid core is easiest to use. 16 AWG is fine. I wouldn't sweat using 18 AWG since you are talking about short runs. There is nothing wrong with stranded, it is just more of a PITA to solder.

You may know this, but be aware that any wire from an inductor is going to be varnished and you need to scrape off all the varnish before you solder.

Got it! Thank you. Yeah I already scraped of the end of the .8mh on the tweeter circuit. I hear you about soldering stranded that is why I was hoping to use solid.
Thanks again!! :T

[tylerdurden]

I have yet another question regarding the xover. Stang maybe you could help me out. What value resister did you finally go with at the R4 position of the tweeter and why? I just ordered the default 1.5ohm. But I am now wondering if I should order a few at a larger value say 2.0ohm. I am bringing this up because I was going over Zaph's blog and he mentions a slight difference in levels being between .75 and 1.5 db's higher in some of the tweeters consistancy.

[stangbat]

As usual, I have a long answer to this. I have switched back and forth. I'm using the Aura tweeter, but I tried out the 2 ohm because I thought the treble was a little much. However, after switching to the 2 ohm, I made some changes to my room and I gone back to the 1.5. So I'm currently running the 1.5 ohm and I don't think I'll be changing it.

Blktre has the NB20FB tweeter like you, and he was also trying to figure out if he needed to switch to the 2 ohm. He had an extended listening session with a friend, and I have also gone over and listened a couple of times. For right now, he left it at 1.5 ohm. He also bought his components right when the flyer came out, so he may not have tweeters that have the possibility of being a little higher in dB.

It wouldn't hurt to have 2 ohm resistors available so you can play around. I don't have a large basis of comparison, meaning I haven't auditioned other DIY designs or a ton of expensive speakers. But on initial listening my ZDT3.5s seemed heavy on the treble. I don't think the problem was the tweeter or how I built the crossover, rather it was probably 1) my room and 2) my skewed sense of what my music should sound like. My ears had been conditioned by years of listening to not so good speakers.

I've also found what Jim Holtz stated in the other ZDT3.5 thread to be true. That is: very little rock music is well recorded. I like rock, but I have to admit that since I built the ZDT3.5s I have found some of the stuff I've owned for decades to be disappointing. And I'm listening to other types of music because it just sounds better now. But I have found well recorded music of all types to sound fantastic on them, rock included. The following sound VERY good in my opinion: Zepplin I, Pink Floyd's The Wall and Wish You Were Here, Full Moon Fever by Tom Petty, 90125 by Yes, and I could go on...

So try the 1.5 ohm and give them a good listen on lots of different types of music. If you think only a few CDs sound strange, then the tweeters probably aren't the problem. If they all sound too bright, then I'd start switching.

[tylerdurden]

I ordered mine right when the flyer came out as well. So the tweets are probably the same batch as Blktre's. I am going to order a few more resistors. I have to order some Deoxit to clean the Pots on my old receivers so i will just add them in.
I probably should have mention this but my theater/listening room is 15'x20' with a 10' ceiling. It is part of a garrage remodel I did a few years back. So it has concrete floors with some low pile carpet and a thick pad. I think the concrete will help. I am looking at wall treatments now. looking at alot of home theater designs online.
All of this is sort of putting the cart before the horse. I really wont know untill I can actually listen/tweek them. It is something I will have to play with. Sounds fun actually, cant wait.
Those are excellent sellection's by the way. We have similar tastes in music. For its time Pink Floyd's The Wall is, IMHO, one of the best "produced" albums ever. And I havnt listened to Yes in a long time. I agree that Rock is, historicaly, badly recorded.
I am almost ready to start building the xovers. It is taking so long because I am a perfectionist and have decided to make the boards look nice even tho they will never be seen. I will be clear coating them in a little while so I can probably start on them tomorrow.
Thank you once again.

[Blktre]

I'm getting ready to place another order w/PE. On that order will be 2ohm resistors. For the cheap money and ease of switching out the 1.5's, its kinda of a no brainer to play around. I suggest using the 1.5 ohm first, give it a decent listen w/various music and sources and play w/room treatments first before switching out to the 2ohm. Ive gone back and forth and listened to Stangs speakers and his thoughts and experience w/these speakers as he was where im at now, and where you will be shortly.

I also agree with others in the other thread about hard rock, bass, etc with the ZDT3.5's. Rock Cd's in general pretty much are not recorded very well. And these speakers show that. Its not a bad thing, its still very listenable, but the Z's are so accurate that after listening to well recorded music, you just feel like something is missing. That goes for mp3's, I-pod's, including some genres of other lossy recordings. I happen to be in HT as well, so im now into the stage of my listening where i can try out 2.1. Sometimes i like the sub, sometimes i dont. Either way the sub gives me an alternative. And i love tools in the toolbox, even if i dont use them all the time.

[Bill Schneider]

Zaph mentions the 1.5, 2, and 2.7 ohm options for tweeter level as you know. I'm going to incorporate all three resistors on the tweeter board as follows:



That way I can switch back and forth between the three merely by moving the input to a different euro connector position. The three different inputs are called INa, INb, and INc in the sketch above.

Saves all the soldering and desoldering.

[Blktre]

Good idea Bill. There should be enuff room for the larger crossover board. Im not a crossover guy, but will having the resistors so close effect anything?
I still say to not get carried away with switching these out on a regular basis until you really have evaluated each and even try some room adjustments as well. I think this will take time to make a fair assessment. Thats why i haven't tried a different resistor as of yet. Btw, when i feel the tweeter is stepping up is on some recordings, not all, and at higher db's (80+). Ive never felt that way at all when listening at moderate levels.

[tylerdurden]

Zaph mentions the 1.5, 2, and 2.7 ohm options for tweeter level as you know. I'm going to incorporate all three resistors on the tweeter board as follows:



That way I can switch back and forth between the three merely by moving the input to a different euro connector position. The three different inputs are called INa, INb, and INc in the sketch above.

Saves all the soldering and desoldering.

You know I thought about doing this as well but wasnt sure how. This is a great idea Bill. So you just solder in all three to the C0 10uf cap then just connect only the resister you want to the terminal strip? Am I seeing this right?
Thank you

[---k---]

Im not a crossover guy, but will having the resistors so close effect anything?.

Only the inductors need to be spaced apart. Caps and resistors are fine as close as you can get them.

[tylerdurden]

Good idea Bill. There should be enuff room for the larger crossover board. Im not a crossover guy, but will having the resistors so close effect anything?
I still say to not get carried away with switching these out on a regular basis until you really have evaluated each and even try some room adjustments as well. I think this will take time to make a fair assessment. Thats why i haven't tried a different resistor as of yet. Btw, when i feel the tweeter is stepping up is on some recordings, not all, and at higher db's (80+). Ive never felt that way at all when listening at moderate levels.

Agreed. I will definately give each an honest amount of time as well as room placement options. Listening distance seems equally important. A minimum of 2 meters is what Mr. Krutke recomends I beleive.

[Brian Bunge]

You know I thought about doing this as well but wasnt sure how. This is a great idea Bill. So you just solder in all three to the C0 10uf cap then just connect only the resister you want to the terminal strip? Am I seeing this right?
Thank you

You connect all 3 resistors to the terminal strip as shown. You merely move your input wire around between the 3 inputs to hear how each of the resistors affects the sound.

[tylerdurden]

"I see"!! said the blind man. :B I will try it. Thank you for sharing this. Sometimes I think hiding the crossovers inside is a shame. I think they could add some asthetic apeal to the overall look, for some people. All be it not practical for the long term. HMMM

[Bill Schneider]

Looks like you understand the approach. The unused resistors are open circuits, not doing anything.

The part of the drawing above that's a bit sketchy is how I will use a solder-type terminal strip to connect parts together in the middle. I've been looking over different crossover builds, and some of the cleverest assemblies are done by Troels Gravensen. He uses solder terminal strips to connect together various components. (Picture below, from Troels' site, is NOT a crossover for this project. However it shows the terminal strips that I will use.)



If a solder-terminal inside is good enough for him, it's good enough for me. I'll still use the screw-clamp eurostyle strips for input/output to enable fast changes.

BTW, Stangbats ZDT3.5 crossover assemblies look really well constructed too. He's got pictures around somewhere on the web.

[Ray Collins]

https://www.htguide.com/forum/showpost.php?p=408485&postcount=220

This is my Statement's CC crossover using terminal strip lugs. It is an old system used for point to point wiring in the pre PCB (my) era. Hope it helps.

Ray