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After reading an article in a popular Audiophile mag, one I try to read most of each month. I felt there was one article that was very different. I again looked over the article and there were a few things that now did stand out as a little light on critique and detail. The article was spread out over a dozen pages or so with a total of 5-7 leaves (verso and/or recto) total dialog. The article title was about a $1M listening room but the article seems more about the trip, buying LP's at a NJ Market, eval of the New Ford Edge and sound system and lots of other critical stuff.

The actual written dialog about the sound room and system, the title topic, consisted of one of two columns on one leaf. The article did mention a few building materials and construction considerations. included were names of the materials and Architects/Engineers and brief mention of "acoustical Engineer" specifically. And there was no real critique as you would expect for such a grand effort. There were some superlatives and even a little emotional stuff about the Wilson Alexandria's but fell way short of a total package critique.... Not like writers to miss an opp to write on and on about all of the details. Like maybe the room was not up to expectation. I don't know but after reading I did come away with a question.

All of that article seems different but I a have a question that leads to my real question.
Can you "Over-dampen a room"? And the real question is:

My speakers sound great (matched pair of B&W DM303's especially) if I am standing 3 ft away from one I cannot tell you which speaker is actually playing what I hear (to a very high degree). If I use 5.1 speakers I can point out the Mission 765's sound track. Will damping improve my speaker invisibility?
If I over-damp will my speakers become obvious or if they are well matched will they disappear even further. I have a sense that all of the speakers flaws will add or multiply.

Thank You

Greg

Read more: When is room treatment needed - Page 8 - Home Theater Forum and Systems -
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Yes, a dead or anechoic room will not only fail to reproduce 3 dimensional sound that envelopes you, but will also be uncomfortable to be when the movie is off.
 

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Yes you can overdamp a room - and you can do it in a variety of different ways.

That said, I have no idea of your situation and would strongly consider looking at speaker/seating position to start with. Unless the room is very very small, what you hear at a 3' distance isn't really relevant to proper imaging.

Can I assume that the Missions are your surround channels or are they a 2nd set of speakers used for HT duties?

Bryan
 

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I'd say this,"it should be harder to over damp an HT with surround sound then one with just stereo." Of course that depends on the program material and how much ambiance the engineer put in there. Many movies I've watched do not have much SS. Fortunately the newer post processing that can be done in modern receivers really helps. I'm shocked at how well it works.

Dan
 

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I was in an anechoic chamber a little while back.. used for automotive testing (Bigger room).

The fact that it is so dead - makes it a little uncomfortable..

Takes a lot of treatment to make a room that dead though..
 

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I was in an anechoic chamber a little while back..
Whilst I have not been inside an anechoic chamber, I have been inside a THX certified dubbing stage with no sound playing and that was so quiet it was a little unnerving.

Yes I believe it is possible to over dampen a room. I have a friend and I think he crossed that line a while ago. The room sounds good, I just think that it could sound better if he had more diffusion and less absorption.
 

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I was in an anechoic chamber a little while back.. used for automotive testing (Bigger room).

The fact that it is so dead - makes it a little uncomfortable..

Takes a lot of treatment to make a room that dead though..
We have an anechoic chamber at work, our main NVH lab (I work for auto OE) for isolating vehicle issues.
You can view those pictures and hear about other peoples experiences, but it truly is...eerie being in there.
I've been in there too many times while launching vehicles and reviewing countermeasures for "issues" and their associated pc cost/tlg cost tradeoffs.
-we need $x.x cost for this dampner to reduce this 3rd order harmonic which is causing this ....which will lead to increase JDpower score unless we act now
etc etc

Our audio guys also have a dedicated room for their vehicle audio testing, but it's more a sound controlled room and an acoustic room.
Sound controlled via keeping unwanted sounds from penetrating into the room while testing. Then, they put different treatments on the inside walls of the room depending on the type of outside environment they want to replicate even while testing inside the vehicle. Its all the vehicle system interaction stuff....
The audio room was built 3 years ago, just as I was building my HT, I enjoyed talking with them while that project was being done, neat stuff.

With that said.....hopefully nobody would just throw treatments around their HT w/o some scientific basis for doing so, that's a recipe for disaster.
Rules of thumb are ok to start as planning, but need to grasp the basis for those before actually doing.
 

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Very interesting Mike..

The chamber I was in - was a little less interesting.... but was at a neat facility -the Center for Automotive Research at The Ohio State University.. Can you say hydrogen fuel cell powered dragster? :) :)
 

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Discussion Starter · #9 ·
Thanks for all of your thoughts and exp. You know I had never considered the effect of an anechoic chamber. I mean I never thought of going that far, but I really wouldn't have too if I put too much damping in, it can have that kind of effect on music frequency segments.

I was thinking of Tx for first order sound reflection and something to optimize wide low frequency effects.

Hopefully at some point in the future I could ask Bryan to give me a few tips. But right now the REW prog is pretty sophisticated stuff. Ive gotta get a mic and start playin'..., haven't even got REW calibrated yet.

Greg
 

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I want to say that the COSI in Columbus Ohio has an area like this, for I remember walking in there and all I could hear was crickets and they were LOUD!!!! Yes...I have tinnitus.:rofl:

Anyway, they would have you clap your hands and the sounds stopped at your hand ....it was crazy.
 

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Yes, but you guys are talking about listening to sounds you are generating yourself from within the room. How about sounds that were recorded in another venue and contain all the appropriate ambient cues to that space? Playing that recording back into an acoustically 'dead' room, I would think, should make it sound very much like you were in that space where it was recorded and not in a 'dead' room. I'm NOT referring to 2-channel stuff that requires reflections from behind the listener but rather 7.1 or at least 5.1 where sound is generated from all directions around the listener thereby providing the appropriate delay reflections without need for reflective surfaces at all to impose your room's acoustical signature on top of the recorded ambient cues. If anything, I think that would muddy-up the sound of the source recording.

My theater sounds pretty spooky dead to anyone talking or clapping etc within the room but the moment a movie starts or music begins playing all that eerieness goes away and you are transported into another space where the sounds are clear and imaging can be almost pin-point... in this respect very similar to wearing headphones except there is a front soundstage and the music is in the room instead of just confined to the inside of your head.
 

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Excellent point Monomer. This brings up the same problem however--not all recordings have a lot of ambient signals. Movies are typically much better than music in this regard. If it's strictly HT, it would be much harder to over damp it. None the less, if you have SS processing, it should be more than doable even in a 'too dead' room.

You got to love technology,

Dan
 

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Yes, but you guys are talking about listening to sounds you are generating yourself from within the room. How about sounds that were recorded in another venue and contain all the appropriate ambient cues to that space? Playing that recording back into an acoustically 'dead' room, I would think, should make it sound very much like you were in that space where it was recorded and not in a 'dead' room.
The goal is to have control over reverberation so that the room itself does not "change" the sound of the recording. You can have too much of a good thing and speakers pending, you might actually need some refection and diffusion for them to sound their best - AKA Dipoles.


My theater sounds pretty spooky dead to anyone talking or clapping etc within the room but the moment a movie starts or music begins playing all that eerieness goes away and you are transported into another space where the sounds are clear and imaging can be almost pin-point... in this respect very similar to wearing headphones except there is a front soundstage and the music is in the room instead of just confined to the inside of your head.
Which is pretty much what I have achieved in my own room. At the screen end, I have no slap echoes and the imaging is amazing. The rear of the room is more live and was needed to get the best from the surrounds.
 

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The goal is to have control over reverberation so that the room itself does not "change" the sound of the recording. You can have too much of a good thing and speakers pending, you might actually need some refection and diffusion for them to sound their best - AKA Dipoles.




Which is pretty much what I have achieved in my own room. At the screen end, I have no slap echoes and the imaging is amazing. The rear of the room is more live and was needed to get the best from the surrounds.



I'm hoping that in the near future I will be placing an order for Kit #1 and #3 from GIK, for my theater is in a concrete basement with tile floor and it needs all the help it can get. The bold above has me confused for bpape suggest putting the monster traps in the rear of the room. Since my listening area will be 12ft across I was planning on putting them 6" apart center rear with 244 x2 on the out side them with tri's in each corner.

So should I deaden the front wall even more so than the rear? Or could I use some 244's maybe x4 across the front wall? I was planning placing 242 at 1st and 2nd reflection points....

Trying figure out what i would need to best tame this room.....and the bold above made me wonder if I know what in the world I'm doing..
 

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Mark, what you have sounds very much like my ideal room. Do you have no slap echo in the rear as well?

Dan
Hi Dan,

No, there is a bit in the back of the room and why I have started adding diffusion. I was going to add more absorption, however research suggested that I am better to keep this end of the room "live" and break up any reflections. In the listening seats, these reflections are not offensive, however I did hear them when standing against a wall near the EQ rack when giving a demo once. I like the idea of "clouds" so might make some of them. I noticed that most hang from chains, so thought I could then even angle the panels.

Overall I am very happy with how the room has turned out (especially considering the low budget I had for this room) so if I am able to make an improvement, all good. If not, then like so many things I do, I remove it and make something else.

I'm hoping that in the near future I will be placing an order for Kit #1 and #3 from GIK, for my theater is in a concrete basement with tile floor and it needs all the help it can get. The bold above has me confused for bpape suggest putting the monster traps in the rear of the room. Since my listening area will be 12ft across I was planning on putting them 6" apart center rear with 244 x2 on the out side them with tri's in each corner.

So should I deaden the front wall even more so than the rear? Or could I use some 244's maybe x4 across the front wall? I was planning placing 242 at 1st and 2nd reflection points....

Trying figure out what i would need to best tame this room.....and the bold above made me wonder if I know what in the world I'm doing..
I did make the front of my room more dead than the rear.

Attached is a bitmap of what my room looks like.



So roughly the 1st 1/3rd is fully (walls) treated and the back 2/3rds are half treated. When I stand in front of the screen and clap my hands, the only thing I hear is the clap. It sounds odd. At the back of the room, I can hear both the clap and some slight reverb. It is not offensive. It seems to enhance the surrounds and why I am reluctant to add any more absorption.
 

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Interesting, thanks for your input Mark. I still have time for I put in an order, just trying to figure out the best way to do this. Once again, thanks.
 

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The Monsters in the rear will address primarily bottom end issues. They're not fully aborptive all the way up.

Bryan
 

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Think about this...

What's the difference between wearing headphones vs listening to your room speakers? The lack of the room's acoustical signature (reflections) because essentially there are no walls inside a pair of headphones and yet I never hear anyone complain that listening to music while wearing a pair of headphones is too dead sounding. To the contrary, I often hear compliments having to do with enhanced clarity and better imaging (except the soundstage is stuck inside your head because you don't have direct sound coming from each speaker reaching both ears with the appropriate delays of course). I'm thinking the room's boundaries actually detract from what is already included in the recording... which is the ambient cues from another space, the space where the recording was made or engineered.

I think the only real dangers with adding more and more absorption are the likely risk of unbalancing the frequency response and also the need to add substantial power to pull the SPL levels back up to where the music will again sound powerful. I think its very hard to over-treat a room but rather what's far more likely is to unbalance the sound if not done properly and also when you remove reflected sound energy from a space it will need to be replaced with more direct sound energy otherwise it will sound too weak and puny and thus could be perceived as 'too dead'.
 

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Monomer, I did a little write up that very much supports your position:
http://dtmblabber.blogspot.com/2011/02/tightening-loudspeaker-recording-and.html

I still haven't addressed the whole issue, but this will give you some supporting evidence. Depending on how things are recorded.... Oye I wish there was a standard. LEDE probably still has an edge b/c it will work well no matter what though not optimally every time all the time.

Dan
 
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