In-wall version of Delta Max

NOTE: This is a variation of the Delta Max. I am not using the same cross over.

I built an AT screen so wanted to take advantage of it.

Cut a hole in the wall. No going back.


I stuffed the space with insulation, even more than shown. The wall is 6" deep including the drywall. The Delta10a has about 1.5" of clearange, which is just enough imo because it has a pole vent. The SEOS12 and DNA-350 just fit. This would NOT work on a 4" wall. That's what I thought I had and was considering 6" woofer ideas until I did some investigating and realized it was 6".

Built a baffle out of scrap MDF. Who cares what it looks like, cause it won't be seen.


Here it is. L and R to come.


Because I designed the delta max already, I was already a step ahead. Finding a cross over that works did not take me long. I've now listened to a 950hz cross over and a 1200hz cross over. Both are very very good and I'm very happy I'm building this as my permanent centre channel (well, permanent is a vague term, right ). The sound is excellent for both cross overs. I'll take measurements soon. It's going to be tough to properly measure in some ways, because I'm confined to indoors. But it'll also make nearfield measurements quite useful being that it's in-wall.

Nice to look at my wall and all you see is a screen. Lurking behind only I know how much power there is.

 

There isn't any bracing... yet. Other than being screwed down to the studs which is really quite rigid. There is a couple cross braces above and below across the studs. It's why there is a hole cutout above, so I could feed the wire past the braces. So there is the rear panel which is drywall, haha. And the baffle is unbraced. Sides, top, and bottom should be fine though.

Once I've worked out the details of the cross over and satisfied myself with the design, I'll take it all out and I'll:

1. Brace it and maybe even totally build a box into the wall. Or I might "rib" the baffle. Not sure yet.
2. Seal it all around. Right now it's just MDF flush to the drywall. No seal. That seems to be ok right now, but not something I want to leave permanently.
3. Paint everything black so any stray light passing through my screen is absorbed.

Believe it or not, I hear "less box" like this than I did with my Delta Max test box. Which admittedly wasn't braced like a permanent build should be, but had a 1" baffle and the usual side to side bracing with a brace front to back between the woofer and waveguide. This inwall version is quite "silent". Maybe it's well damped, because it isn't well braced. Could also be I can't hear the rear panel of drywall, and the baffle is so large and screwed so well to the studs that it doesn't resonate. I don't know, but I was sort of expecting some audible problems. Actually I'd like to hear them so I can know how to go about making the permanent version.

 

Ha, ya, I don't think toe in will be happening. I've thought about how I could do it, but it's basically impossible. 8)

 

DIY spandex. I'll be measuring with and without the screen.

 

Here is an on axis FR spliced with a nearfield around 250hz. Reasonable to do this considering this is in -wall so no baffle step being washed away from that.



Here is the difference from my screen.



So the blue line is what I've been hearing. And it's very good. If there was no screen, I'd probably attenuate the tweeter a little, which there is an easy way to do that.

Will post more details soon. This cross over is fairly simple/cheap

 

Cross over available via pm. Please provide an email address and donate $5 to DIYsoundGroup or a registered charity. Thanks.

 

Coctostan, doing an in-wall was awesome. If I ever move I'm going to have to find a way to do it again. The advantages of the flush baffle are amazing. Really happy with the turn out.

The screen is about an inch away from the drivers. I haven't tried to pull it away cause I can't really.

You're probably right that the less "boxy" sound is because there's no diffraction. Either way, it worked and its great. One of those major improvement type things that don't happen very often.

 

Like this?



Not sure that helps.

Ya, not sure how to implement this as a kit. Having a pre-cut baffle would help people. Something like this is tricky cause it's quite application dependent. It would work the way I've done it, or if someone made a false wall, or surrounds built into the wall, etc.

I think you'd be safe at 1". Maybe even further. The further out the more diffraction is all. You could use this cross over in a box, except it would have diffraction and baffle step and wouldn't sound as good as a result.

 

It's just a DIY spandex. Smokarz has built one and done some testing as well. Pretty slick setup if I can brag. Just a screen on the wall. Wish I had IB subs and then my setup would take less space than a plasma tv.

 

Yes, 16" spacing since north america switched from log houses to wood framed

The depth is pretty ok, which is why I stuck with the 10" woofer. I have clearance for the waveguide too. Only issue is if it's built into a box into the wall, then the CD may bump the back of the box. The woofer will still be mostly ok. I'd use 1/2" for the back panel.

Something like this plate at the bottom of the wall might be handy for people to run wire down between the studs to this plate. http://www.parts-express.com/pe/showdetl.cfm?partnumber=261-352

 

Hey Eyleron,

No one else has built these. I haven't even been asked for the xo. Surprising to me, I kind of thought in-wall speakers would be more popular. And there's been lots of interest in them. None the less, KyleLovesBass has heard it. He was impressed. He also heard my Jack of All Trades in wall. I haven't measured that or documented it yet. He wasn't to thrilled with those, but was looking for something very high end sounding. The Fusion Pure/Max is to big for his application though.

Ok, anyways, installation would be somewhat user built. If your boss is crafty, it really shouldn't be hard to do. Just requires sawing into your drywall ! I kind of stood there stunned before doing it. I hate drywall work and didn't want to create more work than necessary. If it needs to stick out beyond the wall, it may be a good idea to make a 2" wide chamfer to transition from baffle to wall.

This design will run your boss around the $230 mark. Don't worry about a design fee. I don't take fees. Just ask him to make a donation to a charity, or if he already does, as him to write a review you can post. Good or bad. Honestly, not to worried about this one. It really blows me away it's so good. And I gotta tell you, seeing nothing but a screen on the wall is very sleek. When people come over and we hang out in the basement, after about 10 minutes they'll point and say, "what's that". "Oh it's my TV"... Haha. Then I point out the "end tables" and say, those are my subs. They're pretty blown away how WAF it is.

As for surrounds... I'll eventually document the in-wall version of Jack of all Trades. But it is a $95 speaker. If he wants something a little more diffused sounding and higher end, zaph has an in-wall. But again, that's only 86db. If you want in-wall and 90+db, it's gonna be tough to find. Hence why I thought this would be a pretty popular design. If he has anything specific in mind, let me know and I might be able to figure something out.

 

I see what you mean building out the wall behind the screen. That would work good.

The stock baffles could work if you boxed in the studs. That's actually what I did for my L&R. Just slide a piece of 2x4 in there and screw in to the inside of the studs. Do both sides and the cativy goes from 16" to 13". I believe the stock baffle is 14.5" so you'll have 3/4" of over hang. Not much, but workable.

If he's nervous about being a first timer, he could at least pm kylelovesbass for a second opinion. Kyle came over a week ago to hear my L&R and he liked the center.

As for surrounds, by high end I just mean better performance. They're called the Jack of All Trades for a reason. They do it all pretty good. But nothing outstanding. I could probably get them to yield a flatter response, but it would take to many parts. And the waveguide is very short, giving some advantages, but taking away from others. It's also got a lot of diffraction in the waveguide. Higher end would use the EOS8. But, no in-wall xo.

It's about 91 or 92db/w/m and an easy load to drive.