# Wanted: DIY design for shallow, way-bad full range HT speakers



## djbachelor (Dec 16, 2009)

Hi all, I'm working on a plan to optimize my dedicated home theater space and am rethinking speaker selection.

Room is going to be about 13'W x 20'L. The plan was to use Statement speakers behind an AT screen (ported version, and they're half built). Problem is that these speakers really take a lot of space. I don't even mind the cabinet size, which is pretty huge, but they also want to be placed a couple feet _away from the wall_, which would put the screen about 4' into the room. 

The room is long, but I'm trying to save room in the back to squeeze in overflow seating at a bar (i.e. a 3rd row). 

*Q* If I give up the Statements for a 3rd row, Is there a design out there which could save me a couple of feet and _not_ feel like much of a compromise when compared to the venerable Statements? 

Note: I also have an enormous UXL18 Sonosub which demands a low crossover point, so the low F3 on the statements would have been a great match. I might be willing/obligated to trade this out for a couple sealed subs to save more space.)

I am imagining a higher-end DIY design which is sealed or forward ported and won't suffer from being placed close to the back wall and also has high enough output for kick- HT. Maybe even a line array...? I just don't know what's out there these days--I started this venture quite a while ago and need to get back into the game to finish the fight! :boxer:


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## hm-moreart (Mar 5, 2009)

Hello,

look for horns, most working near a wall,
and if possible a corner horn,
the Schalmei-sat ist very small, much SPL, best soundstage,
combined with a corner basshorn or two ...
may be a Klipsch.

take a view on my HP


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## NBPk402 (Feb 21, 2012)

Try the Danley DIY Synergy horn speakers... They are full range and have mids and bass drivers (or some are just doing the woofers and the horn) injected into the horns. If you search google images you will see a bunch of them. I am contemplating making 3 later this year (finances)


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## dgmartin (Oct 29, 2011)

One problem with placement near the front wall is the strong reflections that create cancellation (dips) in the response (when the distance is equal to a quarter or the wavelength). The closer to the wall, the stronger the cancellation but, more importantly, it will move it within the mains’ frequency range or worse into the mid-range. With regards to this issue, the important distance is between the front baffle and the wall (not the port-wall distance unless the port tune is high and the speaker really close to the wall). Any direct radiator speaker will present the same issue since it will always (well, practically) be within the (mid-)woofers pass band.

Probably acoustic treatment of the front wall is a better way to address the issue. It will need some thickness to be effective at these frequencies. I think it should be answered in the “Room acoustics” section.

p.s. It is true that a rear port should have additional boundary gain.


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## djbachelor (Dec 16, 2009)

dgmartin said:


> One problem with placement near the front wall is the strong reflections that create cancellation (dips) in the response (when the distance is equal to a quarter or the wavelength). ...
> Probably acoustic treatment of the front wall is a better way to address the issue.


This is a good point, and I should have mentioned that the front wall is already covered with 2-3 layers of roxul panels which I threw up there for my quick-build version. I might need more to dampen the needed ranges, I haven't gotten into the details yet. 

Horns, huh? I hadn't ever really considered horns--I guess I don't generally find them to be very attractive. (I am not this vain in all aspects of life!) That being the case, this would be the perfect opportunity to employ them (behind a screen) if the performance is a fit! I will do some research. 

ellisr63, Re DIY Danley horns: I initially found a lot of chatter about the Danley Synergy and related models including _talk_ of DIY kits and a lot of DIY efforts to copy the builds, etc. Is there a reference thread somewhere with parts and plans? I am looking for a strong, proven model for DIYers... I don't mind a complex build, but I am not really looking to spend too much time tinkering on this one to figure out what the design should be, if that makes sense.

Thanks for the ideas, keep 'em coming. I'd still be interested in trying a line array (but that may not help my rear wall reflection distance, I don't know).


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## djbachelor (Dec 16, 2009)

dgmartin said:


> One problem with placement near the front wall is the strong reflections that create cancellation (dips) in the response (when the distance is equal to a quarter or the wavelength). The closer to the wall, the stronger the cancellation but, more importantly, it will move it within the mains’ frequency range or worse into the mid-range. With regards to this issue, the important distance is between the front baffle and the wall (not the port-wall distance unless the port tune is high and the speaker really close to the wall). Any direct radiator speaker will present the same issue since it will always (well, practically) be within the (mid-)woofers pass band.
> 
> Probably acoustic treatment of the front wall is a better way to address the issue. It will need some thickness to be effective at these frequencies. I think it should be answered in the “Room acoustics” section.
> 
> p.s. It is true that a rear port should have additional boundary gain.


Another idea here--how about a baffle wall approach with flush-mounted speakers? I could build a full or partial baffle wall 24" away from the room's front wall, filled with bass-trap stuffing, subwoofers and speakers. Seems like I'd come out ahead space-wise, and it sounds like performance could be great with the right speakers. 

Any DIY designs that are good for flush-mounting?


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## dgmartin (Oct 29, 2011)

My earlier post was just to put the rear port placement in perspective in relation to other boundary effects. Normally you just want your mains far enough from the wall so the notch is in the sub passband and the sub near wall so their notch is in the mids.

Let’s start back from your OP:


djbachelor said:


> I am imagining a higher-end DIY design which is sealed or forward ported and won't suffer from being placed close to the back wall and also has high enough output for kick- HT. Maybe even a line array...? I just don't know what's out there these days--I started this venture quite a while ago and need to get back into the game to finish the fight!


Without going into details, pretty much any speakers will suffer from being close to the front and/or side walls since their LF drivers are pretty much omnidirectional and as such will radiate sound and interact with boundaries. So for the LF drivers there isn’t something new. For HF, controlled directivity achieved by modern waveguides makes placement near side walls less problematic. As it happens they are quite efficient and well suited for HT applications. In-wall alleviates the back wall issue but does not give any freedom for tuning once installed (spacing, toe-in...)

The half-completed Statements are 16.5in deep, which is not that bad. I would just put them in the room, start measuring and find the real issues. I think you have enough "knobs" to improve things...

You have room for absorbing materials on (or within) the front wall. You can always close the port and make it a large sealed speaker if it measures better in-room and/or integrates better with the sub. Your AVR also has some EQ functionality. 

Given your potentially large listening area, the next step will be to add more subs so to minimize the seat-to-seat variations. That will also let you set a higher crossover point.


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## djbachelor (Dec 16, 2009)

Just noticed my thread title updated by the moderators: "Way-bad"--is that the best we can do? I hadn't realized that "bad-a**" was such a heinous expletive! Another victim of desensitization by modern entertainment, I suppose. :laugh2:

Anyway, I hear what you're saying about working with the statements--they're not terrible; screen could be 3-3.5 feet from the back wall. Still, I think have seen pro, custom builds for baffle walls a mere 6"-24" away from the back wall, which _could_ be worth it for another 18" in the back of the room. 

Plus I'd get to build another set of speakers. So I'm still interested if anybody knows of great flush-mount DIY designs.


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## Wooderson (Nov 6, 2010)

https://www.trueaudio.com/array/


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## jumper (Apr 8, 2012)

Zaph Audio has an MTM design that has an in wall cross over optimized for flush mounting. I had similiar room constraints when i built my HT. I have used them for about 3 years mounted in the wall directly behind my screen. I just recently had them out to fix a cross over. I took the opportunity to redo the baffle and improve the seal. Heres a pic.


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## jumper (Apr 8, 2012)

Oh, i forgot to add, MadiSound sells the drivers and cross overs.


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## Owen Bartley (Oct 18, 2006)

Have you looked at any of the SEOS designs from DIYSoundGroup? I'd bet that the Fusion 15 Sentinel or Elusive 1099 (or the bigger brothers) would give you some great impact, and most of them aren't too deep. I remember reading about the Statements, and most things said they sounded much better a few feet out from the wall.


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