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post #6541 of 10377 Old 09-01-2010, 05:40 PM
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Quote:
Originally Posted by doublewing11 View Post

Having difficult time finding 1" diffusors.......these are the only two I've found:

RPG Bad Panels which are not true diffusors

or

Auralex which are 1" plastic step wedges.

Are there other 1" thick diffusors that can be recommended?

Thanks


Doublewing11 - have you considered RPG's Flutter Free product found here: http://www.rpginc.com/products/flutterfree/index.htm ? It is 1 1/16" deep which would appear to meet your 1"depth requirement. However, and this might be a deal breaker for you, it really is only effective over 2 octaves from 5kHz-20kHz as per RPG's calculated diffusion coefficient claims.

If all you want to do is kill some flutter echo's then this product will likely suffice as flutter echos tend to be more easily heard in the upper frequencies. But, if you wish to add spaciousness, source width and listener envelopment, then a 1" depth is totally inadequate; aim for 8"-12" or deeper yet to bring the effectiveness down to your room's transition (or Schroeder) frequency, which is likely about 300Hz for residential rooms.

Let us know what you're thinking or planning and perhaps others will chime in with sage advice.
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post #6542 of 10377 Old 09-01-2010, 09:28 PM
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Originally Posted by pepar View Post

I'm sure that it has something to do with aesthetics.

Thanks for replying.........

You hit the nail on the head......

Organizing products for fabric wall............can increase the thickness of back/side wall diffusor treatments needed near seating..........just trying to find products consistent in thickness to the treatments I've purchased for the front of the room.

I've found two inch thick diffusors that would suffice........but are not the same thickness as the one inch absorbers up front.
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post #6543 of 10377 Old 09-01-2010, 09:39 PM
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Quote:
Originally Posted by kevinzoe View Post

Doublewing11 - have you considered RPG's Flutter Free product found here: http://www.rpginc.com/products/flutterfree/index.htm ? It is 1 1/16" deep which would appear to meet your 1"depth requirement. However, and this might be a deal breaker for you, it really is only effective over 2 octaves from 5kHz-20kHz as per RPG's calculated diffusion coefficient claims.

If all you want to do is kill some flutter echo's then this product will likely suffice as flutter echos tend to be more easily heard in the upper frequencies. But, if you wish to add spaciousness, source width and listener envelopment, then a 1" depth is totally inadequate; aim for 8"-12" or deeper yet to bring the effectiveness down to your room's transition (or Schroeder) frequency, which is likely about 300Hz for residential rooms.

Let us know what you're thinking or planning and perhaps others will chime in with sage advice.

There is the goal...............ie. spaciousness, and envelopment for two rows seating for eight.

The wife factor plays in ........therefore, 8-12 inches would not work due to aesthetics! Any suggestions?

I'm all ears......
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post #6544 of 10377 Old 09-02-2010, 03:40 AM
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Quote:
Originally Posted by doublewing11 View Post

There is the goal...............ie. spaciousness, and envelopment for two rows seating for eight.

The wife factor plays in ........therefore, 8-12 inches would not work due to aesthetics! Any suggestions?

I'm all ears......


Get rid of your main restriction - the wife! (Just kidding.)

Have you considered rearranging the seating so that you have three rows of seats - 2 in row one and 3 in rows two and three, thereby allowing more side wall room? Or would this configuration put the back row seats too close to the back wall?

Another thought . . . can you open the drywall to insert a diffuser so that the product's depth is using the wall cavity to reduce the amount that it extends into the room? This way you aren't limited to 1" diffusers which is really not the right way to go.

A semi-circular architectural-looking pillar (i.e. hemi-cylindrical diffuser or polyfuser) will act as a diffuser splaying the sound waves in an approx 120degree arc. (PM me if you want pictures of the ones I've built.) The RPG BAD panels come in a 'round' version and would work. You can build them yourself by buying a Sonotube that come in many different diameters and putting a nice wood panel over it and stain/polyurethane it to match your wife's asthetic eye . . .

What about using a larger room elsewhere in the home? Other than that I'm fresh out of ideas given the 1" depth restriction.
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post #6545 of 10377 Old 09-02-2010, 05:06 AM
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Or use 2" everywhere for consistent thickness. Looks are important but if what you install doesn't work properly ...
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post #6546 of 10377 Old 09-02-2010, 04:39 PM
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Hi doublewing,

You may wish to check out Quest Acoustical Interiors products as well. I have said this before and I'll say it again, IMHO, RPG is best utilized in a commercial environment. They just don't produce products that are "home friendly" nor truely customizable. While they do work (in some...not all applications) they are quite unsightly. Quest products will do the same thing as RPG products but will be far more wife friendly if incorporated properly and you won't have to cut into any walls to accomodate other products...which causes a host of other problems.

Regarding your spaciousness/envelopment requirement, treatment will help to some degree, but there are several additional factors that come into play here such as proper timing and speaker alignment, speaker placement, speaker type can also be a factor here, and system/room layout. Hope this helps! Best wishes!

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post #6547 of 10377 Old 09-02-2010, 05:51 PM
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Quote:
Originally Posted by kevinzoe View Post

Get rid of your main restriction - the wife! (Just kidding.)

Have you considered rearranging the seating so that you have three rows of seats - 2 in row one and 3 in rows two and three, thereby allowing more side wall room? Or would this configuration put the back row seats too close to the back wall?

Another thought . . . can you open the drywall to insert a diffuser so that the product's depth is using the wall cavity to reduce the amount that it extends into the room? This way you aren't limited to 1" diffusers which is really not the right way to go.

A semi-circular architectural-looking pillar (i.e. hemi-cylindrical diffuser or polyfuser) will act as a diffuser splaying the sound waves in an approx 120degree arc. (PM me if you want pictures of the ones I've built.) The RPG BAD panels come in a 'round' version and would work. You can build them yourself by buying a Sonotube that come in many different diameters and putting a nice wood panel over it and stain/polyurethane it to match your wife's asthetic eye . . .

What about using a larger room elsewhere in the home? Other than that I'm fresh out of ideas given the 1" depth restriction.

Get rid of my BEST friend for the last twenty-five years? Not a chance!

Since this is a new construction, nothing is set in stone ...........yet time is ticking away. Ground breaks in November as my home will be part of a "Tour of homes" show the first of June. The home plans are set, but the dedicated theater can still use some tweaking........
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post #6548 of 10377 Old 09-02-2010, 06:28 PM
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Quote:
Originally Posted by SierraMikeBravo View Post

Hi doublewing,

You may wish to check out Quest Acoustical Interiors products as well. I have said this before and I'll say it again, IMHO, RPG is best utilized in a commercial environment. They just don't produce products that are "home friendly" nor truely customizable. While they do work (in some...not all applications) they are quite unsightly. Quest products will do the same thing as RPG products but will be far more wife friendly if incorporated properly and you won't have to cut into any walls to accomodate other products...which causes a host of other problems.

Regarding your spaciousness/envelopment requirement, treatment will help to some degree, but there are several additional factors that come into play here such as proper timing and speaker alignment, speaker placement, speaker type can also be a factor here, and system/room layout. Hope this helps! Best wishes!

Thanks for the input SMB..........

Your input several months ago literally stopped me in my tracks...........since then, your suggestions have taken me in another direction.

I'm an independently minded person and really wanted to get involved with putting this theater together. I'm close to understanding what I want/need in terms of budget and aesthetics.....and will summon the help of a designer to put it together once I'm 100% sure of my goals and path of implementation.

Yeah, I know............room first, but can't help myself in regard to audio equipment. Would love to audition the Procella brand, but with that said, am heavily leaning toward either Aerial (LR5/SR3) or Triad (Gold Monitors/Gold surrounds) for implementation.

One step at a time...........................
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post #6549 of 10377 Old 09-03-2010, 04:08 AM
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All three of these speakers you've noted are excellent and happen to fall on my favorites list. The Procella, however, uses a compression driver which will provide better HF performance over greater seating distances than Aerial/Triad. Within reasonable limits a determining factor between Procella and Aerial/Triad could be seating distances.

SMB mentioned Quest Acoustical Interiors (www.QuestAI.com). They have a unique two inch product marketed under the name PerfSorber. It is an excellent absorber and diffusor which works better (and measures better) than you'd expect from a 2" material. We've used that in several high performance projects to excellent results. (One of which was the THX Certified room in New Jersey.) [NOTE: PerfSorber is not available except from QuestAI ... there is a fresh patent on it.]

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post #6550 of 10377 Old 09-03-2010, 09:56 AM
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Quote:
Originally Posted by Dennis Erskine View Post

All three of these speakers you've noted are excellent and happen to fall on my favorites list. The Procella, however, uses a compression driver which will provide better HF performance over greater seating distances than Aerial/Triad. Within reasonable limits a determining factor between Procella and Aerial/Triad could be seating distances.

SMB mentioned Quest Acoustical Interiors (www.QuestAI.com). They have a unique two inch product marketed under the name PerfSorber. It is an excellent absorber and diffusor which works better (and measures better) than you'd expect from a 2" material. We've used that in several high performance projects to excellent results. (One of which was the THX Certified room in New Jersey.) [NOTE: PerfSorber is not available except from QuestAI ... there is a fresh patent on it.]

Thanks for the comments Dennis.............

I might be naive', but without a listen the Procella products do scare me a tad bit............I'm still hemorrhaging from a Klipsch audition. Horn or waveguide tweets............ they are all the same to me ie. loaded horns. I will defer to the experts on deciphering the differences.

Thanks for the Quest Acoustic Interiors url............not as much information as the MSR site, but I will take your word as gospel in regard to product performance and will contact dealer in Washington State.

This product search/research is a pain, but hopefully in the future it pays off. Sad but true, there are no real affordable turnkey solutions for home theater construction in Oregon..........if I was in California, different story.
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post #6551 of 10377 Old 09-03-2010, 10:17 AM
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Largely the problem with horns is they can take your head off if you're sitting too close to them. It can easily be a seating distance problem.

If you're coming to CEDIA Expo, Procella will have a life demo running.

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post #6552 of 10377 Old 09-03-2010, 10:58 AM
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Quote:
Originally Posted by doublewing11 View Post

Horn or waveguide tweets............ they are all the same to me ie. loaded horns.

No they are not.
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post #6553 of 10377 Old 09-03-2010, 12:48 PM
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No they are not.

Ok..............

Please elaborate............

Though I'm not an expert in the audio/video realm.........I do have an extensive background in both mathematics and physics which helps in understanding underlying principles and properties.

If I'm missing something, I'm all ears as I want to know/learn the difference.


Btw, a note to others..................what are the underlying differences in overall quality and execution between the two acoustic distributors Quest and MSR?

Thanks
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post #6554 of 10377 Old 09-03-2010, 05:05 PM
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Originally Posted by doublewing11 View Post

Ok..............

Please elaborate............

Though I'm not an expert in the audio/video realm.........I do have an extensive background in both mathematics and physics which helps in understanding underlying principles and properties.

If I'm missing something, I'm all ears as I want to know/learn the difference.

All the information is out there if you choose to look for it. A simple equation describing a flare's shape barely begins to define how it will sound. You need to study the drivers as well and how they interact to form a system and how that interfaces with a room. You have a lot of research ahead of you.

My earlier response was akin to: because you have heard one implementation of horn loaded drivers (tractrix flare with cheap CDs) then they all sound the same. I have owned several Klipsch models and heard more and they are far from the best representations of their type.
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post #6555 of 10377 Old 09-03-2010, 05:56 PM
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All the information is out there if you choose to look for it. A simple equation describing a flare's shape barely begins to define how it will sound. You need to study the drivers as well and how they interact to form a system and how that interfaces with a room. You have a lot of research ahead of you.

My earlier response was akin to: because you have heard one implementation of horn loaded drivers (tractrix flare with cheap CDs) then they all sound the same. I have owned several Klipsch models and heard more and they are far from the best representations of their type.

Never thought of the Pallidiums worthy of playing cheap CDs.........

Well...........I guess I'm guilty of not liking the Klipsch sound...........but am open minded enough to give other similar designs a shot.

Guilty as charged.......btw, I enjoy ribbons and fabric dome tweets.......
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post #6556 of 10377 Old 09-03-2010, 06:03 PM
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CD=compression driver

Not hear the Palladiums myself, but almost everything else.
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post #6557 of 10377 Old 09-07-2010, 02:59 AM
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Quest and MSR

They both produce high quality products.

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post #6558 of 10377 Old 09-18-2010, 08:14 PM
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I couldn't figure out a good place to post this, hope I got it right.

My room is 32x17.5x9' and I have been using it while under construction. For the last year one of my long walls has been simply 5/8" sheetrock on standard studded wall.

I'm using two Danley DTS10's and have actually been a little displeased with performance. Over the last few days I got R13 placed into that entire long wall. Since this change, my wife and I have both noticed improved sub performance. It's all a bit tighter, more percussive and extension seems improved.

Are we imagining this? or is there some reasoning behind our findings? With my limited understanding, could it be that the bare sheetrock wall just let the sub frequencies right out into the rest of the basement? Maybe now the sheetrock plus R13 is helping to keep the energy in the theater a bit better? Would adding the sheetrock on the outside of that wall help even more?

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post #6559 of 10377 Old 09-19-2010, 03:49 AM
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When you're outside the room, can you hear the sub? There you go. The insulation is doing next to nothing as far as sound transmission outside the room. The insulation would be reducing resonance inside the wall cavities which is helpful.

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post #6560 of 10377 Old 09-19-2010, 05:23 AM
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I'm not trying to accomplish sound isolation. It means nothing in my arrangement. But I do welcome any acoustic benefit inside the room.

If I didn't know better, the subs are reacting to this as if prior to insulation they were trying to pressurise the entire 2000sf basement.

I would not have guessed that resonance in the wall played this large a role.

Thanks for your input Dennis.

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post #6561 of 10377 Old 09-19-2010, 07:26 AM
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Tony,

I don't mean to oversimplify or to speak for Dennis as he and the other pros can explain this far better than I can.

What is going on is, as you said, your subs are trying to fill the entire basement. This is because the low tones produced by your subs are passing straight through the walls. The insulation you installed did very little to stop this but as you now know, it is dampening the resonance within the wall. Although there are great benefits outside the room by isolation, what is often understated are the benefits inside the room with isolation. The most accepted and easiest way to do this "sound containment" is double layers of sheet rock inside the room. You will also hear improvement when you install the sheet rock on the outside of the wall.

Since you had only one layer of sheetrock over the studs inside the room and the other side was open, you essentially had a giant drum the subs were striking with each note. This was producing the resonance you had and still have to some extent. Until the wall is "rigid", this resonance will still occur to some degree.

For now, I would concentrate on installing the sheet rock in the hallway to close the wall. I could be wrong and the pros can lead you better than I but at the moment, it's probably where you will get the best "bang" for the buck.
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post #6562 of 10377 Old 09-19-2010, 10:07 AM
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Since you had only one layer of sheetrock over the studs inside the room and the other side was open, you essentially had a giant drum ... Until the wall is "rigid", this resonance will still occur to some degree.

Yes, though there's more going on as well. An un-damped sheet rock wall does resonate and ring. But when the cavity is stuffed with insulation that sympathetic resonance is damped. So you actually get some bass trapping / absorption. But a large room like that needs more bass trapping inside the room to get even tighter and flatter bass.

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Thanks Dan and Ethan. The "drum" theory makes alot of sense. It may be a few months before I can close in that wall completely, but I look forward to any additional benefit.

Ethan, I do have the typical OC703 triangular corner traps on two wall to wall corners in the front of the room (floor to ceiling). I recognize that this is a small dent in what the room size demands. My final treatment plan will include the wall/ceiling connection at the front and rear walls. Beyond that I would be making aesthetic sacrifices that I don't want to make.

BTW, Ethan I've enjoyed your online videos time and time again. Thank you.

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post #6564 of 10377 Old 09-20-2010, 11:08 AM
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Thanks Tony. I'm in the final throes of a third music video now, though it will not show 20 Ethans playing instruments!

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post #6565 of 10377 Old 09-27-2010, 01:39 PM
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At CEDIA one of the chaps at the THX/Procella Sound demo recommended a "baffle wall" be built so that wall-mounted speakers be as flush as possible and cutouts be 1" larger than the speaker and the 1" gap filled with foam. He said that there would be a 6dB gain by doing this. Is there any truth to this?

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post #6566 of 10377 Old 09-27-2010, 03:29 PM
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Quote:
Originally Posted by pepar View Post

At CEDIA one of the chaps at the THX/Procella Sound demo recommended a "baffle wall" be built so that wall-mounted speakers be as flush as possible and cutouts be 1" larger than the speaker and the 1" gap filled with foam. He said that there would be a 6dB gain by doing this. Is there any truth to this?

Jeff

I don't know about the 6dB gain, but this is a great idea for controlling sound waves that follow the speaker baffle surface until they reflect off something, causing out-of phase reflections. DIY speaker builders often put absorptive materials around speakers, especially the tweeter. This is just doing it for the whole speaker.
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post #6567 of 10377 Old 09-27-2010, 04:38 PM
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Quote:
Originally Posted by erkq View Post

I don't know about the 6dB gain, but this is a great idea for controlling sound waves that follow the speaker baffle surface until they reflect off something, causing out-of phase reflections. DIY speaker builders often put absorptive materials around speakers, especially the tweeter. This is just doing it for the whole speaker.

That was indeed one of the benefits as he described it; sound that would follow or be radiated by the cabinet up, down, to the side or rear would be eliminated. The THX/Procella demo, with the baffle wall, was the second best demo we heard. Harman's demo had free-standing speakers and was third. Wisdom Audio's demo was the best and theirs had in-wall speakers. I'm not saying that that was the variable that made the difference, just observing that the two best sounding demos had "flushed" speakers.

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post #6568 of 10377 Old 09-27-2010, 08:03 PM
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Yes Pepar, there is truth to this, and Audyssey has nothing to do with it! By flush mounting, you increase the sensitivity of the speaker, thereby increasing the ouput of the speaker given the same amount of wattage. So, if you increase the sensitivity by 6 dB by flush mounting, you also increase the efficiency and the ouput is equal to the increase in efficiency....therefore an output increase by 6 dB. This, of course, depends on a perfect world, and there are other factors which may cause actual values to fluctuate, etc, etc. I am sure we will here the faint whine of circular saws buzzing away way past midnight tonight as everyone rushes out to build a baffle wall. If only Home Depot was open 24 hours. P.S. Gotta razz you on the Audyssey thing now and again.

http://www.thx.com/professional/cine...d-baffle-wall/

Shawn Byrne
Erskine Group
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post #6569 of 10377 Old 09-27-2010, 08:46 PM
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Originally Posted by SierraMikeBravo View Post

Yes Pepar, there is truth to this, and Audyssey has nothing to do with it! By flush mounting, you increase the sensitivity of the speaker, thereby increasing the ouput of the speaker given the same amount of wattage. So, if you increase the sensitivity by 6 dB by flush mounting, you also increase the efficiency and the ouput is equal to the increase in efficiency....therefore an output increase by 6 dB. This, of course, depends on a perfect world, and there are other factors which may cause actual values to fluctuate, etc, etc. I am sure we will here the faint whine of circular saws buzzing away way past midnight tonight as everyone rushes out to build a baffle wall. If only Home Depot was open 24 hours. P.S. Gotta razz you on the Audyssey thing now and again.

http://www.thx.com/professional/cine...d-baffle-wall/

The THX link seems to be related to a movie theater, but I suppose it scales down to a home theater. That I heard it in a small room seems to confirm that. A 6dB increase in output is HUGE! And nearly free.

Should the baffle wall be covered with diffusion? It seems odd to leave it untreated.

I deserve a shot every now and then on my affinity for Audyssey.

Jeff
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post #6570 of 10377 Old 09-27-2010, 08:55 PM
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Treat with absorption the same way you would with any front wall. How much absorption...well I'll keep that one under wraps. A girl has to have some secrets!

Commercial THX theater...home THX theater...what's the difference? Best wishes!

Shawn Byrne
Erskine Group
HAA Design Certified -THX Certified Professional

Design-Video & Audio Calibration Information

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