Acoustical Treatments Master Thread - Page 56 - AVS Forum | Home Theater Discussions And Reviews
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Old 09-28-2006, 07:51 AM
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Wow Brent, looks terrific. I think the rounded edges are a great touch. I only have 2 questions:

1) How are you planning on mounting them to the wall?

2) Did your rigid foam have a paper backing like 703 does? If so, what did you do with it?
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Old 09-28-2006, 08:40 AM
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Felgar - Thanks for the comments. I guess the edges could also be rounded with a router. Problem is, I don't own one.

This is a works in progress so mounting has not yet been determined . First thought is to just hang them over a couple of nails that are 5/8" proud of the wall. Nails would fit in gap between upper horizontal cross piece and fiberglass. The heads of the nails would provide a lip to help stop them falling off. However, these things are fairly light (or more accurately, have a high surface area to weight ratio) so I am not all that concerned about what would happen if they fell of the wall. Would be more of a "thud" than a "crash". The alterative would be to make little flat plate hangers, or perhaps use a short length of chain (anything that is an inch or so long and has a couple of holes) that could be screwed into both the frame and wall.

I am yet undecided if I am going to put some sort of cloth backing on the these. Once on the wall, the fiberglass cannot fall out. And the fibers seem fairly well bonded......

The rigid fiberglass I used was "unfaced". 703 is for sure available unfaced as well.

Brent
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Old 09-28-2006, 03:59 PM
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I am just starting planning after months of reading. I have a room 22x22x10. (I know square is not good). Do I need to build 2x4 walls with GG and two layers of sheetrock or will the 12" cement walls keep sound from traveling. This room is under a garage with an 10" slab. Only one entry door and three sides totally underground and one side into the rest of the house. Was thinking I could just put strapping on walls and not sheetrock? Will this work or do I need to frame walls? Thanks
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Old 09-29-2006, 07:32 AM
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I am on going to buy 1" Linacoustic to line the lower half of my side and front walls. I finally found it locally. I will have some left over. Can I make panels out of this (stuffing it into frames), instead of buying rigid fiberglas panels (which I am having a heck of a time finding locally)? Just trying to save cost, and to use what I have. Also, how is everyone dealing with with outlets once you mount and cover the Linacoustic? Cut holes in Linacoustic and cloth cover, and then extend the outlets 1" from the drywall? With speaker wires, RCA outs, and electric outlets, I'm not sure it will look right (e.g., nice and flat). Any thoughts on how to deal with this issue?

Thomas
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Old 09-29-2006, 11:33 PM
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Ya'll seem pretty detailed. What's wrong with a little Quietrock sheetrock on the walls and Quietwood on the floors? Seems a lot simpler.
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Old 09-30-2006, 10:58 AM
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Let me start by saying that it is a little intimidating entering a thread where some of the participants are clearly experts in their field, and are willing to go to great lengths in the pursuit of perfection. I've been plowing through this thread a little at a time over the last couple of months while in the planning stages for the re-do of my basement, and would like to get your opinions on getting the maybe 85-90% of perfection that I think should be realistically and easily achievable in my circumstance.

I'm dealing with a typical tri-level basement, not very large with ceilings that are about 7'6" when finished. This will be a VERY mixed use room - more than a dedicated home theater. In fact, I will probably do more (casual to serious) music listening than movie watching. I'm building a bar at one end and shoe-horning in a 7' pool table next to that. There will be a number of compromises as a result of everything we are attempting to do, but my goal is to achieve the best acoustic response I can, with the greatest range of usability for the room.

This room had been "finished" by the former owner of the house, and I first had to undo pretty much everything they did. So far I've torn down the sheetrock (which never had the seams taped,) reframed most of the walls (which had stud spacing anywhere from 12" to 20" on center as the mood struck,) and redone the electrical (which could have burned down the house.)

At the end of this post is my hand drawn sketch of the room. Sorry, but I haven't had time to work on this project more than 1 1/2 days a week on average, and I didn't want to spend a couple of days trying to figure out how to use SketchUp.

I'm going to put R-13 behind the drywall and in the ceiling, and was going to put 2" OC 703 behind the stage area. OC 703 superchunks in all four corners (above and below the two rear corner speakers.) I know that putting the rear surrounds in the corners is not optimum, but windows, the pool table, and other space considerations make that compromise necessary. Ditto for the side surrounds.

Finally, my thought was to cover the bottom 40 or so of the right side wall and rear wall with fabric we have picked out that is fairly heavy and passes about 50% of the acoustically transparent breath test. Behind the fabric would be 2 OC 703 for a padded wall effect. On the left side of the room there is almost no available space for doing the padded wall thing.

I was thinking that using 2 703 on the side and rear wall instead of the 1 that seems to be more the norm on these forums would make up for the lack of 703 on the left wall. In the end I decided to ask for informed directions before I got too carried away with my assumptions.

Thanks in advance for all the time and information you all share with these groups. Immediately after this post I'll post a panoramic picture of this space as it looked last week, taken from the bottom left corner of the sketch.
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Old 09-30-2006, 11:04 AM
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Here is a panoramic shot of the carnage so far. This picture was shot
from the back corner of the bar (lower left-hand corner in the diagram.)
That big empty space on the left side will be a 90 gallon saltwater reef tank someday.

The wall studs are not really crooked, that and some "ghostly" tools are from the stitching program I use.
A seven foot (bar size) pool table will be going to the right of the
bar, and a curved leather sectional sofa will be in front of the Plasma, angled slightly towards the upper right-hand corner of the room.

Don't laugh, you should have seen this room a week ago!

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Old 09-30-2006, 11:50 AM
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Quote:
Originally Posted by texas teacher View Post

Ya'll seem pretty detailed. What's wrong with a little Quietrock sheetrock on the walls and Quietwood on the floors? Seems a lot simpler.

These products are used for sound isolation -- to make your room quiter, and allow less sound to escape to other rooms. They do not improve in-room acoustics, as do absorber panels and other sound treatments. You need both. Sorry that it is even more complicated.

Oh, and for sound isolation, you can't just do one part of a room, because sound will happily travel right through the areas you haven't done. So a "little Quietrock sheetrock" becomes "a lot" -- enough for all your wall surfaces and ceiling.

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Old 10-09-2006, 01:10 PM
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I've put up some pics and diagrams of my project and have several questions about Positioning Acoustic Panels in an Apartment. I could really use some of the brainpower in this thread. Thanks in advance.

Please comment in this thread:
http://www.avsforum.com/avs-vb/showthread.php?t=734181

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Old 10-09-2006, 11:31 PM
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Quote:
Originally Posted by patrickjherbert View Post

Let me start by saying that it is a little intimidating entering a thread where some of the participants are clearly experts in their field, and are willing to go to great lengths in the pursuit of perfection.

Sometimes I think the thread ought to be unstickied. Many views expressed at the beginning by some of the "experts" have probably evolved considerably. The use of absorption for one is over rated in this thread. (And absorption that defies room symmetry has thankfully never been highly rated.)

Firstly, one is no way NEAR perfection in terms of acoustics if the loudspeaker being used is shoddy. Clearly enthusiasts ought to be demanding better but the infatuation with loudspeakers featuring primitive easily saturated passive crossovers continues. There are indeed very few consumer loudspeakers with the requisite on and off axis flat frequency response.

Once you start with a superb loudspeaker, it's better to optimize reflection and diffusion in the horizontal plane. Early reflections can aid musicality and speech intelligibility. Diffusion affords an enveloping passive surround that complements active surround of multichannel setups. Screw the linacoustic. Any absorption, reflection or diffusion ought to be as broad in bandwidth as possible lest it unbalance the off axis prowess of the loudspeaker being used. Whereas reflections may work laterally, the front and rear reflections are best attenuated or diffused (the latter preferred with adequate distance from diffusor -quadratic residue or prime root- to listening seat). Bass distortion is the worst offender in typical rooms and the ceiling/or wall ceiling corners is a strategic choice for broadband bass traps. The rest of the ceiling can be interspersed with broadband diffusion and absorption. Tortuous calculation of reverberation times is hogwash. With a treated ceiling and furniture, one may already have enough absorption to get away with hardwood floors and area rugs. The Welti/Toole configuration of multiple subs and parametric eq of peaks below 300 Hz should round out amelioration of bass distortion not fixed by broadband bass traps and drywall flex.

Most of this is a far cry from the linacoustic loving advice you'll find in this thread. Balance out whatever advice you typically would get here with what Richard Bird, Russ Berger, John Storyk, or Floyd Toole would advocate (even though they're not always right). Google away.
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Old 10-10-2006, 11:05 AM
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Tumara,

That's a great post and I agree with almost everything you said. I too don't understand why this was even made a sticky in the first place. It's way too much for anyone to digest, it's full of contradictory and often wrong opinions, and the signal to noise ratio is low.

> enthusiasts ought to be demanding better but the infatuation with loudspeakers featuring primitive easily saturated passive crossovers continues. <<br />
Indeed. And you don't have to pay an arm and a leg for excellent speakers.

> Early reflections can aid musicality and speech intelligibility. <<br />
I read that in Dr. Toole's paper but I disagree. Even Dr. Toole left that "conclusion" open to interpretation. We can continue that in another thread if you'd like to start one.

> Tortuous calculation of reverberation times is hogwash. <<br />
Agreed 100 percent. Most domestic size rooms don't even have reverb.

--Ethan
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Old 10-10-2006, 09:47 PM
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Are stages and risers in HT rooms bolted/nailed/screwed to the floor? I would think that they're not so as to decouple them from the floor. But in so doing arent the stage and riser susceptible to movement considering that its not attached to anything? Also is it ok if I only put sand only for the stage where the speakers and sub will be and insulation inside the risers?
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Old 10-11-2006, 06:38 AM
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Originally Posted by ciotime View Post

Are stages and risers in HT rooms bolted/nailed/screwed to the floor? I would think that they're not so as to decouple them from the floor. But in so doing arent the stage and riser susceptible to movement considering that its not attached to anything? Also is it ok if I only put sand only for the stage where the speakers and sub will be and insulation inside the risers?

FWIW, my riser is not attached to te floor, but it is of sufficient weight that it might as well be. And my LZBoys, feet cradled in "channels," are held only by gravity as well. I constricted the outer frame of the riser from 2 x 12's and the cross members from 2 x 10's effectively suspending the top. I had done this thinking thAt I might add a bass transducer at some point in the future, but it resonates on it's own at around 25Hz so nicely that no active driver is required. Check my link and navigate to the appropriate page to see how I did it.

"The future is already here, it's just not evenly distributed." W. Gibson

"I like the future, I'm in it." F. Theater
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Old 10-11-2006, 06:51 AM
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Quote:
Originally Posted by Ethan Winer View Post


> Early reflections can aid musicality and speech intelligibility. <<br />
I read that in Dr. Toole's paper but I disagree. Even Dr. Toole left that "conclusion" open to interpretation. We can continue that in another thread if you'd like to start one.

> Tortuous calculation of reverberation times is hogwash. <<br />
Agreed 100 percent. Most domestic size rooms don't even have reverb.

--Ethan

I've experienced the exacty opposite with absorbers at the first reflection points - ALL first reflection points - making a HUGE difference in the intelligibility of music and speech. Which brings me to agreeing that many diverse, and diametrically opposed, opinions being expressed here by seemingly educated and well-meaning individuals so that confusion reigns - at least in my head.

I know I need to control bass peaks resonances in my 13 x 21 x 8 room, but am I now to believe that decay is not important because I don't have any reverb? Should I try to add some? Too dry is no good - I've read that 300 milliseconds is a good target for midband.

"The future is already here, it's just not evenly distributed." W. Gibson

"I like the future, I'm in it." F. Theater
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Old 10-11-2006, 07:42 AM
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pepar,

I think your "I came, saw, got drunk" sig is having an effect. I can't tell which side you're taking here:

> I've experienced the exacty opposite with absorbers at the first reflection points - ALL first reflection points - making a HUGE difference in the intelligibility of music and speech. <<br />
I'll take it you agree that adding absorption helps intelligibility? That's sure been my experience and the experience of every single person I've ever helped. The text below is from a post I made elsewhere not long ago. (Sadly, those who could not stand to hear opinions that contradict their beliefs locked the thread...)

> am I now to believe that decay is not important because I don't have any reverb? <<br />
A room that size still has "decay" issues that need to be addressed. Besides modal ringing which is tamed with bass traps, there are also first reflections. The difference between decay in a small room and real reverb is more of a technical distinction.

--Ethan

Quote:


Floyd is brilliant and I agree with most of what he wrote. I enjoyed the article tremendously, and learned a lot too. I hope to read it again at least once if not twice.

Perhaps the most important thing I learned is that "Generic 'good' listening room ratios are a myth" for which he makes a compelling argument. However, his point does not seem to apply for a playback system having bass management if the subwoofer is in a corner, as in my living room HT. I never experimented with four subs, one in each corner, but I suspect the same thing applies there too. If all the modes are activated equally, their ratio should indeed still matter.

I did find a few more things to comment on. In the opening Floyd wrote:

Quote:


At low frequencies the long-standing problem of room resonances can be alleviated substantially through the use of multiple subwoofers, thereby providing similarly good bass to several listeners in a room.

If you define "good bass" as a flat response, I agree that multiple subs can help. But that does nothing to reduce modal ringing which is at least as damaging as a skewed response, so having multiple subs is not a complete solution. I'm still waiting for proof that modal ringing can be reduced by EQ for an area larger than one cubic inch.

I also think his comparison of music in a concert hall in the context of why we don't mind longer reverb decays is flawed. That's fine for opera and symphony concerts, but it's not relevant for pop music or jazz where the bass instruments are recorded either direct or with a microphone very close. In that case you do not want excess ringing or decay because bass notes can run together losing clarity and articulation.

Likewise, he seems to equate "good" but very late reflections in a concert hall that make the orchestra appear wider than it is, to side wall reflections in a home listening room. This defies my own experience, where absorbing those reflections makes the sound stage wider, rather than the other way around.

Quote:


Strong directional features were associated with early reflections.

Sure, and this returns us to whether the listening room should impart its own character onto the playback, versus all desired ambience is already in the recording so the room should add nothing further. The latter approach is the only way a recording can be heard as intended in different rooms. I contend that all needed and desired localization is (or should be) already present in the recording through the use of panning and reverb and ambience effects added by the mix engineer.

Quote:


All of this is clearly relevant to localizing the real sources - the loudspeakers. However, success in doing this may run counter the objectives of music and film sound, which is often to "transport" listeners to other spaces.

Exactly. In a listening room you do not want to localize the sound as coming from the loudspeakers. Untamed reflections defeat this goal. It is very easy to demonstrate that in my own living room, and I do this all the time for visitors. If you stand behind the couch outside the Reflection-Free Zone you can clearly identify the speakers as the sound source. If you then lean forward over the couch the sound stage opens up, becomes wider, and you no longer hear the speakers as the source. (Except maybe for instruments panned all the way left or right.)

Another thing he seems to miss is why a small room seems to sound better than the measurements would imply. As I see it, the reason we can enjoy music in a room that measures excessive comb filtering is because the comb filtering is very different for each ear. He keeps trying to make it sound like the brain is some mysterious processor that is able to make sense of sound even when the comb filtering response is so poor. As Occam would say, I have a simpler explanation: The frequencies missing in one ear due to comb filtering are mostly present in the other ear simply because the ears are far enough apart. Later in the article Floyd seems to recognize this because he observed:

Quote:


Gilford ... concluded: "The fact that the listening room does not have a predominant effect on quality is very largely due to the binaural mechanism." ... we measure differences that we seem not to hear.

Were we to measure at two locations six inches apart (ear spacing) and combine the results, I believe that would more closely resemble what we hear.

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Old 10-11-2006, 09:26 AM
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Quote:
Originally Posted by Ethan Winer View Post

pepar,

I think your "I came, saw, got drunk" sig is having an effect. I can't tell which side you're taking here:



Quote:
> I've experienced the exacty opposite with absorbers at the first reflection points - ALL first reflection points - making a HUGE difference in the intelligibility of music and speech. <<br />
I'll take it you agree that adding absorption helps intelligibility? That's sure been my experience and the experience of every single person I've ever helped. The text below is from a post I made elsewhere not long ago. (Sadly, those who could not stand to hear opinions that contradict their beliefs locked the thread...)

On this, I'm on your "side."

Quote:
> am I now to believe that decay is not important because I don't have any reverb? <<br />
A room that size still has "decay" issues that need to be addressed. Besides modal ringing which is tamed with bass traps, there are also first reflections. The difference between decay in a small room and real reverb is more of a technical distinction.

I'm not sure about the side on this one because I am still a bit confused on the terminology. Does not a room with "decay issues" have a "reverb" problem?

"The future is already here, it's just not evenly distributed." W. Gibson

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Old 10-11-2006, 11:39 AM
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How do you handle First Reflection points for Surrounds and rear (Dipole). Are they not suppose to follow the wall a little?

Or should you address these with some treatment?

Thank you
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Old 10-11-2006, 12:03 PM
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How do you handle First Reflection points for Surrounds and rear (Dipole). Are they not suppose to follow the wall a little?

Or should you address these with some treatment?

Thank you

I think dipole surrounds are supposed to reflect from the surrounding surfaces to develop the soundfields.

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"I like the future, I'm in it." F. Theater
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Old 10-11-2006, 04:38 PM
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So if I have a 13 foot wide room and 24 " face base traps in each of the back corners (Floor to Ceiling) it will leave me about 10 feet for a flat back wall. If the rear speakers are on the back wall about 5-6 feet apart will there be enough room between the outside driver of the dipoles shooting towards the base trap. (approx 2 feet from base trap)

thank for the help.
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Old 10-11-2006, 06:17 PM
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Quote:
Originally Posted by KERMIE View Post

So if I have a 13 foot wide room and 24 " face base traps in each of the back corners (Floor to Ceiling) it will leave me about 10 feet for a flat back wall. If the rear speakers are on the back wall about 5-6 feet apart will there be enough room between the outside driver of the dipoles shooting towards the base trap. (approx 2 feet from base trap)

thank for the help.

I like dipole surrounds in a 5.1 system to be on the sides for movies. If I listened more to music I'd rather have monopole (or tripole) speakers in the back.

I'm pretty sure I didn't (directly) answer your question. How far from the rear wall is you back row of seats?

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Old 10-11-2006, 10:28 PM
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I consider Ethan an authority, and his views are duly noted. In any case, I recommend anyone on an acoustics forum to read Toole's paper for themselves: Loudspeakers and Rooms for Sound Reproduction - A Scientific Review, J. Audio Eng. Soc., Vol.54, No.6, June 2006. This paper is excellent and will prove to be seminal for years to come.

Toole does not upend the conventional wisdom for using side wall absorption; to lock an image in place. If anything, he and Olive have demonstrated in earlier studies how varying the amplitude and delay of lateral reflections affects our perception of spaciousness and image shifting and spreading. He further allows room for standards of reflection control to be developed for multichannel configurations. That said, the paper is unequivocal in enthusing about early lateral reflections.

"Persuasive evidence points to several beneficial and few negative effects of early reflections" ... "Multiple reflections improve the audibility of timbral cues from resonances in the structure of musical and vocal sounds" ... "Early reflections improve speech intelligibility" ... "Early lateral reflections increase our preference for the sound of music and speech. Individual reflections in small rooms may be too low in level to have the optimum effect, thus providing opportunities for multichannel sound"

A notable caveat: Toole insists that for the precedence effect (whereby the brain correctly localizes a sound source in the wake of strong early reflections) to work, the tonality of the direct and reflected sounds should be very close. "If the spectrum of a reflection is different from that of the direct sound, the probability that it will be heard as a separate spatial event is increased - not a good thing." In that case, for most audiophiles with their allegedly cool loudspeakers, the drawl of an Alabama Sheriff upon meeting up with a wrongdoer ought to apply; "Tell you what son, yo ass is s*** outa luck!" They are better off sticking with OC 703 and calling it a day. I might point out that Toole's findings seems to be in line with the observations of those who have designed (or reviewed) highly accurate systems with an excellent polar response, such as teams behind DEQX/ NHT Xd, Seigfried Linkwitz and his Orion, and above all my guru Peter Aczel.

Frankly, I'm not technically inclined enough to argue the merits or otherwise of early reflections in small rooms. I just wanted to give fellow enthusiasts a glimpse of what's in the paper and strongly urge them to read it themselves. As always, I'm in utter awe of Toole's scientific flair. He ruffles many an arbitrary belief, and boy isn't that a lot of fun.

Tumara Baap
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Old 10-11-2006, 11:44 PM
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Pepar, my rear speakers will be about 6 feet from the back of the seating area about 1.5 -2 feet above the ears. The same height as the sides.

So if you can picture the back wall like I tried to describe firing about 2 feet from a corner base trap on each of the outside drivers. and about 6 feet apart (inside driver) from each other mounted on the back wall.

I will probably not do anything with that drywall that the speakers will be mounted two but just had some concerns on the outside drivers and the corner base trap.

TumaraBaap, I will look into that......thanks
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Old 10-12-2006, 03:43 AM
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"Flabbergasted" is what I'd like to title this post.

This is probably my first post in this thread/forum. I'm still in reading and learning mode, but have digested enough info that I'm ready to tackle accoustic treatments in my new basement/HT room.

I've spent the last 3 days calling every local (Baltimore) insulation provider listed, and most of the "Home Theater" installers, too, searching for a source of OC703/705. What have I succeeded in? NOTHING. What have I learned? I have learned that there is a shocking lack of knowledge and experience in room treatments. A good 1/2 of the "HT installers" I spoke to don't do anything with regards to room treatments. A salesmen at the local Tweeter was completely in the dark, and most of the insulation supply houses don't carry it or want to sell me something completely unsuitable for the application. They all think I want to "soundproof" a room. In short, you guys are making me look like I'm the one who's nuts!

I could buy OC703, oh sure, if I wanted to order a truckload. I need about 30 sheets. So, until I find a suitable local supply, (help anyone? please?) I've had to order it off of the internet, which cannot be anywhere near cost effective.

Flabbergasted. But I'm sure its worth it. You should hear my new 20'x25' room with its bare walls, YIKES! Eww!

Thanks for letting me get that out there. I feel much better.
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Old 10-12-2006, 05:45 AM
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Originally Posted by Schwingding View Post

I could buy OC703, oh sure, if I wanted to order a truckload. I need about 30 sheets. So, until I find a suitable local supply, (help anyone? please?) I've had to order it off of the internet, which cannot be anywhere near cost effective.

Schwingding-
I had similar issues until I found SPI. I'm not sure what the closest location is to you (Lancaster, PA?), but I was able to get boxes (24sheets) of 2x4 OC703 1" for ~$80. 45cents/sq.ft. was better than any other price I found.

You may want to look into that:
http://www.spi-co.com/servicecenterdirectory.cfm
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Old 10-12-2006, 07:07 AM
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Originally Posted by MarkMac View Post

Schwingding-
I had similar issues until I found SPI. I'm not sure what the closest location is to you (Lancaster, PA?), but I was able to get boxes (24sheets) of 2x4 OC703 1" for ~$80. 45cents/sq.ft. was better than any other price I found.

You may want to look into that:
http://www.spi-co.com/servicecenterdirectory.cfm

That link should be in a master list of references! One call to the Lancaster office and I was speaking with Rick Remington, who proved extremely knowledgable, friendly, and willing to help out on a small homeowner sized requirement. You just made my day, thank you!
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Old 10-12-2006, 07:15 AM
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Pepar, my rear speakers will be about 6 feet from the back of the seating area about 1.5 -2 feet above the ears. The same height as the sides.

Sooo, this is a 7.1 system?

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Old 10-12-2006, 07:47 AM
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Originally Posted by TumaraBaap View Post

A notable caveat: Toole insists that for the precedence effect (whereby the brain correctly localizes a sound source in the wake of strong early reflections) to work, the tonality of the direct and reflected sounds should be very close. "If the spectrum of a reflection is different from that of the direct sound, the probability that it will be heard as a separate spatial event is increased - not a good thing." In that case, for most audiophiles with their allegedly cool loudspeakers, the drawl of an Alabama Sheriff upon meeting up with a wrongdoer ought to apply; "Tell you what son, yo ass is s*** outa luck!" They are better off sticking with OC 703 and calling it a day.

It seems ludricrous to me to think that for the sound reflected off a sheet of drywall, the wall itself would have little to no effect on the tonal characteristics of the sound. The wall is not perfectly smooth and will also vibrate, thus adding it's own sound to the reflected sound. Even differing wall constructions will yield different behaviour so I don't see how the reflected sound could be considered close to accurate. The ceiling is probably even worse, suffering from (typically) less accurate vertical off-axis dispersion of the speaker and a surface that's not nearly as smooth with a typical stippled construction.
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Old 10-12-2006, 07:54 AM
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Originally Posted by Schwingding View Post

That link should be in a master list of references! One call to the Lancaster office and I was speaking with Rick Remington, who proved extremely knowledgable, friendly, and willing to help out on a small homeowner sized requirement. You just made my day, thank you!

I, too, bought my OC703 from Rick. Did you know he has a musical and recording studio background? A few others in the office as well.

"The future is already here, it's just not evenly distributed." W. Gibson

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Old 10-12-2006, 08:14 AM
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Yes it is 7.1,

so basically I would have 1 side of each of the 4 dipole surrounds firing towards a Corner Base trap. I see this a lot on some of these theaters but what effect does that have on Dipole for surrounds.
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Old 10-12-2006, 10:28 AM
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Originally Posted by Schwingding View Post

That link should be in a master list of references! One call to the Lancaster office and I was speaking with Rick Remington, who proved extremely knowledgable, friendly, and willing to help out on a small homeowner sized requirement. You just made my day, thank you!

So how much did everything cost, does he ship?

I went with ejdavis.com, based in CT, who shipped 2" unfaced 703 in cartons of 6. I bought 12 2x4 sheets @ 77 cents/sqft. Shipped in 2 boxes, my total was $118.94.

ejdavis was a much better price than I found anywhere else, and though I can't afford any more right now, I'll probably be building some more panels in the future. So far, simply putting a single panel at the first refelction points on my left and right walls produced a noticably more clarity in center channel dialogue. I've started recommending this to everyone,and by far the most complicated part of the whole process is finding 703 at a decent price.

Listen to the Real HT Info Podcast at http://realht.info, including video reviews at my YouTube Channel: http://www.youtube.com/user/realhtinfo/videos
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