Hey Aging Attorney!
No hard feelings and my intention was not to be so agressive in my responses (must be those new testosterone stimulating vitamins and herbs, I've been taking)
I too have been around the block a few times and I'm sure I'm years older than you so my "aging" moniker applies to me also.
And regarding the "precedence effect" it is only so effective. If a room is a cacophony of reflected sound even "it" will not help, so I am a strong beleiver in adequate room acoustics, acoustic treatment, set up and preparation.
Hope to see you again under less contentious and more constructive circumstances. |
Nearfield listening is avoidance of the inherent in room acoustic problems and blinds the listener to the boundary limits of the recorded soundstage. Tom |
Summitav, I owe a debt of gratitude to you for allowing me to understand the precedence "affect". I went to the Audio Physic's site and boy is my German rusty! Thank God I found a link to the US distributor's site were I learned the following about this phenomena:
"This intelligent approach to acoustic perception is the reason why, in former times, we were able to run in the opposite direction from a sabretooth (sic) tiger, in the middle of a thick forest with many reflections rebounding from trees."
We wouldn't be around now to talk about this were it not for that "affect".
BTW I have been called worst things than an "aging attorney", which is quite factual I might add.
I hope you and the original poster enjoy your respective systems and AP speakers.
Maybe this issue of whether near field listening making room integration of speakers so much easier should be the object of its own thread. I leave that up to you since you seem to have a way with words and have given me reason to believe you are a member of MENSA and could present the question in a very credible way. With all due respect, I remain, an aging attorney. |
In case you thought my response to Pbb was just to him, i have pasted my response to you in a seperate post.
I am rather familiar with your speakers and the designer. I concur with much of his design philosophy and set up parameters.
The Audio Physic Virgo is a speaker designed by Joachim Gerhard who is a master at soundstage and imaging.
Your speakers should create a well developed soundstage and sonic images. They should virtually "disappear".
The Designer suggest that you listen nearfield (6' is his suggestion which is "very" nearfield) and "if possible" set the speakers up on the "long wall" so that you have no sidewall reflections.
Both of these suggestions will reduce room interaction and reflection as I suggested.
Gerhard also suggests sitting rather close to the rear wall (which I might have reservations about unless you treat the rear wall) but the 2 feet he suggests will probably be fine.
Below is an exact quote of the Designers set up prefernces fo this speaker:
Gerhard's ideal setup is you against the long wall (room permitting), speakers 8' apart and 6' from the listener. This way the speaker is closer to you than it is to any wall: the first thing you hear is the speaker, not the room—thus, the room is effectively taken out of the equation. The only wall in play is behind you and closer than 2', so it's effectively out of play.
Try the desingers suggestions and see if it helps. If you want to read more about set up of your particular speaker, look here
http://www.stereophile.com/showarchives.cgi?147:3
All the best and sorry about the insolence. |
Pbb,
I did not say that nearfeild was a panacea for anything. I said that it along with proper treatment will offer the best reduction of room interference.
You on the other hand say that unless you wear the speakers as headphones nearfield is a waste of time.
Then you obfuscate with some dazzling "speed of sound" questioning which clearly demonstrates your lack of knowledge.
There is nothing I have written that says I don't beleive in room acoustics, but in "real life" the problem of room interaction and direct sound needs be approached from both directions. Just like an aging attorney to "try" and adjust the contention.
If you remember correctly the poster already had begun room treatment and it was not totally successfull. My suggestion to go nearfield was perfectly logical and did not eliminate additional room treatment if nessessary.
It was quite obvious you just wanted to see your contentious response as an authority in print.
Your assertion that a speaker designer "must" consider that his product is going to be used in a room is a lesson in the obvious, but no designer can design a speaker to work in "all" rooms. There is no "drawing board" or speaker that "fits all" by design.
Now to Outlier - The Audio Physic Virgo is a speaker designed by Joachim Gerhard who is a master at soundstage and imaging.
Your speakers should create a well developed soundstage and sonic images. They should virtually "disappear".
The Designer suggest that you listen nearfield and "if possible" set the speakers up on the "long wall" so that you have no sidewall reflections.
Both of these suggestions will reduce room interaction and reflection.
The Gerhard also suggests sitting rather close to the rear wall (which I might have reservations about unless you treat the rear wall) but the 2 feet he suggests will probably be fine.
Below is an exact quote of the Designers set up prefernces fo this speaker:
Gerhard's ideal setup is you against the long wall (room permitting), speakers 8' apart and 6' from the listener. This way the speaker is closer to you than it is to any wall: the first thing you hear is the speaker, not the room—thus, the room is effectively taken out of the equation. The only wall in play is behind you and closer than 2', so it's effectively out of play.
So Pbb, yes I do have it figured out since this is also generally one of my set up goals.
And to Outlier, try the desingers suggestions and see if it helps. If you want to read more about set up, look here
http://www.stereophile.com/showarchives.cgi?147:3 |
Gbmcleod,
Thanks for the clarification! No damage done. |
Great to know that you have it all figured out Sumitav. Precedence effect notwithstanding, I maintain my position that anyone who does not believe that room acoustics is, to steal a line from our good friends at Ford, Job One, is sadly mistaken. Your initial short post seems to clearly indicate that some people listen to the room and some to the speakers. Hogwash! Any speaker designer who does not take into consideration that a speaker will be used in a room should go back to the drawing board. Insofar as the original post is concerned, clearly the room treatment used does not satisfy Outlier. Many posters have suggested what they consider will improve the situation. Your near field suggestion is valid to a certain extent. Your suggestion that it is a panacea and precludes taking care of room acoustics is another case of throwing out the baby with the bathwater. As far as your Bose comment, I will not dignify it with any of my own, except to say that it has to be cheapest way to get a pop on sites such as these. My last recommendation would be to go with the room placement suggested by the manufacturer. Thinking ahead, properly implemented mc systems should, hopefully, cure many of these collapsed sound staging situations. |
Bombaywalla:
I assure you that I wasn't suggesting that your advice was incorrect in any way. Consider my comments an addendum to yours, in case Outlier wanted to use Tube Traps. I've seen them placed wrongly in many rooms. Even reviewers install them wrong, as when Tom Miiller of TAS had RoomTunes in his room and wrote an article about the designer coming into his room and completely changing their position. Also,in an old issue of TAS, HP averred that the Tube Traps were helpful but that the instructions were not. Moncrieff's article is the best one so far. |
Hi Folks:
Thanks again for all the additional suggestions. I have the Virgos set up based on Audio Physic recommendations, although not their ultimate preferred position (which is 50% the way into the room), but rather just 25% into the room from the back wall, and 25% away from the side wall (the room is not a dedicated listening room, so I need to compromise a little). I could experiment further with the toeing though. Seating position is almost against the back wall. I'll try the side wall absorbtion suggestion when I get a chance - will need to make the panels though, as there is no wall to attach them to in the appropriate area of the side wall (a corridor on one wall, and a wall of full length windows/ curtains on the other side wall). I guess the idea there would be to minimize side echo/distortions on the sound, allowing the ear to focus on the primary/first sound waves which come directly from the speaker?? Seems reasonable, if that's the logic. I can try and experiment with tube traps later, but my room characteristics make that difficult - the door opens on the far left of the room (preventing the addition of a tube trap there because it would be an obstruction in that corner). Other far corner is bookshelves on either side of the corner (probably good defraction anyway). Near left corner is desk/PC etc, and near right corner is bed. Hence, no good places for tube traps (in corners anyway). Center of ceiling is an overhead fan, so not good for any treatments there, but I guess I could put some before or behind the fan (would absorbtion be of any use there, or would it cause more problems?) Anyway, thanks again for all the great input. Getting the room right is challenging. To answer an earlier question - I don't feel I'm trying to solve any apparent problem with the sound. Rather I just want to get the most out of my room and improve the sound if possible. The sound is absolutely amazing from my perspective - I guess I'm always trying for better though, as I'm sure we all are.
Cheers. |
Outlier -- that's a good system you have there. Try placing the speakers 60 degrees apart (from listening position) at a position where the Virgo toe-in is b/ween 70-72 degrees (i.e. speakers parallel, facing you, is 90d).
That's (allegedly) the Virgo system testing position. I've tried it in a rectangular room & it's good. Cheers |
Don't overlook the very interesting ideas on speaker placement from Audio Physic itself. I don't have Virgos, but I did end up with a setup essentially consistent with the AP approach. This should be your starting point, as it intends to eliminate the room as much as possible. Then you can experiment with treatments, if necessary, to deal with what's left. Check out their website. |
To Pbb,
Yes, I know how fast sound travels and have studied acoustics enough to know why nearfield is a valid method of reducing the effects of reflected sound.
It is quite obvious you don't understand the "precedence effect" and how it works.
It is also obvious that you don't understand the differences between direct and reflected sound and how the ear/brain interprets them.
Just so you completely understand my position, I suggest using reasonable room treament to reduce reflection to a minimum and listening nearfield to reduce exposure to what is left.
And the speed of sound really has nothing to do with nearfield listening or reflected sound since the moment sound hits something its amplitude is adjusted down, by absorption and dispersion.
When a sound hits an object part of it is reflected in a dispersive pattern, obviously in a different time/phase domain and some of the energy is absorbed (turned to heat energy)
The sound from the speaker that travels directly to us does not suffer from this, and is what your brain takes as real and if the amplitude is adequate, it takes precedence when the brain interprets the sound.
The resulting mismash of sonic haze from reflection/dispersion is no match if one is listening nearfield.
Maybe if I make this simple you'll understand.
Take a flashlight and set it atop your speaker. Turn off all the lights in the room and notice that in your listening postition the light shine on your face and some of the light disperses to the side walls, in fact it gives "low" light to all the room.
The beam in your face is direct. The one at the wall is reflected/dispersed. The fact that the light is traveling at the same speed does nothing to reconstruct the reflected light and make it a threat to the direct light.
Sound has the same properties, just at lower frequencies.
In a room, your goal is to reduce the reflected and maintain the direct.
So maybe you use Bose 901s and this doesn't mean anything, cause your listening to mostly reflected sound anyhow.
I don't know what experience you have in setting up rooms, but if you think you need to use headphones for the best sound, it would seem not to many. |
The near field thing will never make proper room acoustics redundant. Headphones will do that. So unless you are prepared to attach your speakers to your head, no amount of near field mumbo jumbo will negate the need to have the best acoustics possible for the room. Getting a good room to start with is probably just as important, but, like most everyone, we don't necessarily have a choice of rooms. To Sumitav: have you any idea how fast sound travels and the fact that it bounces all over the room, whether you are fifteen feet away from the speakers or six? How long do you think you get to hear the first arrival wave? |
It is quite obvious that you are used to listening to your room, as well as your system.
Assume a "nearfield" (7-9feet) listening positions adjust your speakers exactly on axis, leave all treaments exactly as they are, and be prepared to hear your system, instead of room reflections and false ambience.
You will also have to use reasonable volume 75-80db or more to attain the precedence affect. |
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Gbmcleod,
Indeed you are correct in saying that tube traps cannot be placed along the wall & then be forgotten. They must be tuned. I didn't go into that in my post as the main objective there was to introduce him to the product more than teach him how to use it.
Yes, that classic article from J. Peter Moncrieff is a killer article. I have read that article many times. Once again you are right - many people just don't use the traps correctly. Turning them 2" at a time is indeed too much! BTW, that tube trap article is available on ASC's website too: www.acousticsciences.com & click on "articles". Both the 1985 & 1989 papers are there. This is seminal work done w/ tube traps & worth reading every page of.
FWIW. |
For those contemplating such devices, take a look at the "non-linear absorption characteristics" that such devices introduce into your listening room. While most people install these thinking that they are going to help the sonics out, all they do is create even greater irregularities in terms of what you hear. Chances are, not only do you have a screwed up room to begin with, you've now introduced even more irregularities into the equation as frequency changes. Take a gander at this and then come back and read the rest of this post. For most installations, you'll want to look at the green line on the chart. RPG Pro Foam Absorption coefficientsIf any of you saw that and thought that it looked like a mess in terms of frequency response, think again as it is even worse than what you think. Rather than providing you with room acoustics that would resemble what is provided on that chart, you have to flip it upside down to see what the in-room response would be like. This is due to the fact that they are showing you how much absorption takes place at a given frequency, not the actual "frequency response" that you would hear. Once you look at it upside down, you can see that these "acoustic treatments" create a very big "suck-out" in the 500 Hz to 1250 Hz range and reduce all frequencies above 1250 Hz to a very noticeable extent. Most everything below appr 400-500 Hz passes through untouched. As such, the very "life-blood" aka midrange of the music is damped / absorbed and all the artifacts of treble reproduction ( air, spaciousness, harmonic structure ) are reduced. On top of this, the rate of attenuation is NOT linear across the band so you end up with peaks, valleys and ripples as the signal is spread out across various frequencies. Since bass is not affected in the least, the warmth region and bottom end remain consistent with what you had before installing these devices, but now everything sounds thicker, more distant with less "sparkle" up top. Tonal balance has shifted drastically and NOT in a linear manner. As such, the end result is that you've created another form of acoustic non-linearity in your room and paid $150 for $5 worth of "flimsy molded foam". If you keep spending at this rate and buying devices like this with no real plan of attack or understanding of what you are trying to achieve, your system should be completely unlistenable in no time flat. Rather than throw your money away on J-U-N-K like that, invest in a book or two by F. Alton Everest and look at your room like you would your system i.e. as a WHOLE. Once you have a better understanding of what is going on, visiting such sites as those put together by Jon Risch for DIY room treatments and acoustic engineers such as Rives Audio will give you the ability to do things yourself and / or get professional help to diagnose what you really need to do. Rather than throwing money away in a random fashion and creating new problems to deal with, you can get to the root of the problem much simpler, faster and cheaper without as many drawbacks or side-effects taking place along the way. I hope this helps some of you to realize that "audiophile approved" items are not necessarily "good" and that, many times, you can learn / do / build something better yourself for a LOT less money. As i've said before, there IS a place for "specs". That is, so long as one knows how to interpret them AND the manufacturer has presented them in an honest fashion. Sean > PS... I think that Agon member "Tom_nice" has various plans for bass traps, room treatments, etc... that also work quite well. You might want to try contacting him for further info. Hopefully he doesn't mind me doing this, as he's offered th same thing himself several times in other room acoustic related threads. I also know that Tom is a "fan" of Everest's books too, as they are about the best that you'll find on the subject for the amount of money spent. |
The Tube Traps are very helpful in taming room acoustic problems. I know; I've had 30 of them since 1988, when Stereophile first reviewed them.
HOWEVER, you can NOT simply place them and forget them. You must tune them carefully, by moving them along the side wall (if that's where you are using them). Try moving them 1/8 inch at a time, with the reflective side facing into the side wall, and them rotating the seam TOWARDS the speaker.
For a more detailed setup of them, go to Peter Moncrieff's classic article on Tube Traps. Here's the website: http://home.wanadoo.nl/thingman/trapart4_u.htm
This is an EXCELLENT article on how to optimize the Tube Traps. I used it to great effect when I had WATTS (the first 3 generations of them).
You can also buy some RealTraps, which I recently purchased. They are as effective (in the bass especially) as Tube Traps. Their website is: www.realtraps.com. They are MUCH less expensive than tube traps and work quite well at ceiling/floor junctures, as well as placed in corners. I was quite surprised at how much they cleared up the bass range; I put the Tube Traps in the same positions, and they're about equal in their effectiveness. HOWEVER, the tube traps have the advantage of absorbing AND reflecting, while the RealTraps, which work as well, don't allow for tweaking. The good thing about the RealTraps is that they come with a 30-day money back guarantee, so if they don't work well (unlikely), you can request a refund. I can tell you that a few people at TAS are using them, and I'm loaning a couple of mine to the Sea Cliff gang (although, they could clearly ask for their own!).
Finally, the Tube Traps, once you place them along a wall, MUST be rotated in tiny, tiny, TINY increments. Forge about 1/2 inch rotation: I'm talking about a 1/100" rotation. Trust me, it changes the sound in quite tiny increments. I think, as HP said in a past issue, that people don't use them right at all. They turn them 2" at a time: WAY too much. You'll have to experiment with them. It's the difference between good and excellent when you rotate the columns. |
Outlier,
I'm not surprised to read that you have had a miserable time w/ these foam acoustical treatments! When I was in the market for acoustical treatments, the $150 package was mighty tempting in lieu of buying ASC tube traps. In hindsight I'm happy that I didn't buy these foam treatments & bought the ASC tube traps instead. These traps are awesome & have done wonders for my room & as you rightly said, they are phenomenonally expensive! I had mid-bass & upper-bass boom that needed treatment.
1st, you never told us what was wrong w/ your room! What are you trying to correct for or are you just jumping on the acoustical treatment bandwagon? Different issues require materials & some of the room issues just cannot be solved with passive materials (& require a TacT or Rives-like unit). It would be nice if you could (anyways) let us all know what you were trying to achieve.
Foam panels are acoustic velocity absorbers ie. they absorb higher freq. & high freq, usually above 400Hz. It is no surpise here that they "deadened" the sound! These panels absorbed the high freq & left you with the mid-bass & lower thereby giving you a dead-like sound. BTW, for acoustic velocity absorbers to work, they must be placed atleast 4" from the wall where there still an acoustic velocity of the sound wave! Once the acoustic wave hits the wall, the velocity goes to zero & the foam panels do not act on a zero velocity wave. In contrast, ASC tube traps are acoustic pressure absorbs (bass is acoustic pressure). One hemisphere is reflective & is used to reflect 400Hz & higher. The cool thing about ASC tube traps is that when one uses it to reflect 400Hz & higher that reflective surface is away from the wall by the diameter of the cylinder. This occurs naturally as the reflective side faces the room (rather facing the wall surface)!! So, one doesn't need to make stands or any such thing to get the reflective side to work correctly.
My suggestion to you (as some others have also pointed out earlier) is that you keep some panels to treat the 1st reflection off the side wall next to the speakers. Here, make a 4-ft tall frame from 2X4 from Home Depot. Make a stand for this 4-ft tall frame so that you can free stand it anywhere in the room. Attach 2 2'X 2' panels (to create a 4' tall X 2' wide) using Velro to this frame. Place these panels in front & to the wall side of the speaker so that it can "treat" the 1st side wall reflection. You will have to play with exact position. Now, I have assumed that your tweeter is not higher than 4' off the floor. If your tweeter is higher then you will have to make taller panels or simply raise the 4' tall panels off the floor.
Like the others, I do not recommend using more panels behind the rack/back wall or behind your listening seat - it'll deaden your sound as you have already found out. Use them only if your room is very lively.
For bass traps, you can roll your own. Try Jon Risch's receipe. In yahoo! search for the name "jon risch" it should bring up his website. There is tons of very, very good info there. I have found his info to be accurate (he is trained as an acoustics engineer) & my friends have used his panels receipe with great success.
IMHO. FWIW. YMMV.
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So, it's all in your head?... :-) |
No, no, how could I be a contrarian? I never yes, I never say no, quite the contrary. |
Well, folks I think I solved the complex room treatment challenges...... by removing the *$(%&#@ treatments altogether. From the effects I was getting, it's hard for me to see how these absorbtion treatments can have any benefit. I'd still be open to experimenting with tube traps and defraction type treatments (although those two seem like pricey experiments compared to the cheap foam), and I'm still of the opinion that room set (especially speaker placement) up can have a huge impact on sound quality. That said, I think I'm done with this foam stuff. Thanks to all for the suggestions though. Cheers,
Outlier. |
Sorry Sir,
Fres le jaque, fres le jaque, de main vous, de main vous... |
You guys are cracking me up and disturbing the class at the same time. Sit up straight, look forward and pay attention : ) Sean
> |
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Are you saying I am a contrarian? |
Since when you are not? :-) |
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It's all in your head... :-) |
Chairs with foam padding - a good example is the Ikea Puoang chair, otherwise an attractive & inexpensive chair - can have the same deleterious effect on sound in the room as Sonex & similar foam type wall treatments. |
... and of density in the materials used is required. Trial and error is called for. Diffraction on the wall behind the listening position is way better than absorption. (seems this portion was missing from my initial post, not that it matters, but) |
From what I understand, AP speakers tend to be balanced for listening in the nearfield. How close is your sitting position to the speakers? If you are in the farfield with speakers balanced for the nearfield and then damp the room as well, the result could be overly-dead sound. Just a thought...but you should go into much more detail about your entire physical set-up than you have so far... |
You don't want to absorb the sound behind the listening position i.e. diffraction is much better there.
As far as the type of "room treatment devices" that you are working with, these do more harm than good due to their non-linear absorption characteristics. I would send them back to Audio Advisor and read up on the subject before wasting any more time and money. Sean
>
PS... i think that there was a thread here on Agon regarding "biggest rip-off in audio" and i cast my vote for "Pro-Foam" type "room treatment devices". $5 ( at the very most ) for materials that they sell you for $100+ dollars and all it does is whack up your listening room. J-U-N-K !!! |
The first thing that came to my mind was to remove the foam from behind the listening position and move it behind the speakers in order to enhance the LEDE aspect. The suggestion of trying to reduce the sidewall reflections by placing them there is also quite valid. Trial and error is the order of the day. The room is the most important factor in proper sound reproduction. Quite ordinary equipment can produce quite extraordinary results in a good environment, the converse, unfortunately is also quite true and often found. A variety of surfaces |
Have you read a discussion about increasing the air flow of an intake manifold? Redirecting what is traped by right angles is more science than art.. Dampening is not frequency selective, it will kill the dynamics as well as the music..Think outside of a box then maybe it won't sound like one..Oldie Tom |
Rives: Yes, you are correct about the LEDE setup that I tried to describe. I didn't go into enough detail to mention that my "inverted LEDE" setup was actually the opposite of the original studio arrangement. Thanks for catching that. And since I've making a second post, let me mention that I used a modified reverse "LEDE" acoustic treatment in a small, dedicated audio room back in the late 1980's. At the time, I owned a pair of Acoustat 2's, and I had a bad echo/reverb problem. I placed a pair of Tube Traps in the corners behind the speakers, and also put a pair of 2'x2' Sonex panels on the wall directly behind each speaker (to tame the rear sound wave). The majority of the sound treatment was directly behind my listening couch, however, with several 4'x8' panels of Sonex (varying thicknesses). This combo of materials did an excellent job of taming the room problems, and yielded very satisfying sound reproduction. |
I can't think of anything good coming out of reflective surfaces - it will just cause you to hear a signal at about the same intensity arriving slightly later than the original signal - this will cause brightness and a loss of transparency. Just the opposite of what you did with sound absorption panels and just as bad, if not worse. What you can also do with the set up you now have is to try changing the toe-in of your speakers, radically at first, from say 30 degrees from pointed straight at you to pointed straight ahead and crossed well in front of you. This latter could help you avoid the potentially negative effect of the glass doors. If space allows, I would put in well stocked bookcases behind the listening position as a cheap method of diffusion. (in my room I use them on both side walls and the rear wall. I use large plants on the wall behind the speakers). Keep the faith, this is all done empirically. What ever works is good and every room is different (as are your expectations. |
I have used many types of sound treatment over the years from many different manufacturers. All have their problems. Using nothing is better than most. Redirecting the air flow geometrically in my room, mostly on the ceiling and atop the speakers has greatly enhanced the sound of my system. These are my latest acoustic adventures. All the dampening crap is long gone.. Want to know more..Tom |
Thanks folks for the comments so far. Some interesting possibilities. Just to mention, while I can put some absorbtion material on one of the side walls, it won't be symetrical with the listening position and the speakers (they will need to be closer to the listening position, as there is a corridor in that area of the side wall). Also, the other wall is all glass door, with curtains between. I could attach the material to the appropriate part of the curtains, but that seems like stretching things a little. I guess I could try the ceiling as well.
Overall, from what I've heard it really seems like the panels have only deadened the sound - I somehow have my doubts about any benefit they're going to offer. I'll try removing them from behind the speaker, and then maybe try the opposite as well. I'll also try removing them and adding more to certain areas. It still seems like a big confusing mystery though. I wonder would the addition of some highly reflective surfaces (rather than absorbant surfaces) made a positive difference. Cheers,
Outlier |
Rather than putting them behind the speakers, try putting them on the side wall at the first reflection point. Since they are 24x24, I think 2 or at most 3 on each side should be enough. After that, put 2 or 3 in the middle of the front wall and 1 or 2 at the first reflection point on the ceiling. |
Acoustics can be tricky. Actual acoustical measurements can make a tremendous difference in designing a room, but even without them if the room is basic (rectangular and no openings) then basic math and experience can yield a good result. SD's advice is also good, but there is a small correction. LEDE originated from studio control rooms. The live end was behind the listener and the dead end behind the speakers. This is good for control rooms--but bad for listening rooms. The LEDE method that SD describes is actually the inverse of the original LEDE--but it is the one that I agree with for audiophile listening rooms. It allows short reverberation times near the speakers which adds to ambiance and it controls the long reverberation times behind the listener. I could go into a very lengthy discussion on the philosophy of this, but I think most people would fall aspleep. The other thing is that applying only one type of acoustical treatment, in your case high frequency absorption, generally does not yield good results. You need to judiciously deal with the entire range of frequencies from low, mid, to high. I'm not really surprised that things sounded dull and calapsed after applying this material--you need to do some other things as well most likely. Our listening room, a basic tutorial on room acoustics, may provide you with some insite: the listening room |
take away the treatments behind your seat---put in diffraction. absorption behind the seat usually kills presence. |
Not nearly enuf info in your post to be helpful to you, but FWIW my order of priority in setting up diffusion (not deadening) materiels for dynamic speakers is sidewall reflection points first, behind the listener 2d and behind the speakers last. I'd remove the panels you now have, piece meal in that order and see what happens. Good luck. |
Room treatments can be a very tricky process, and without conducting a real-time analysis it's hard to know exactly what's required. The best suggestion I can offer is to try treating your room with the "LEDE", or "live-end, dead-end" approach. The LEDE approach usually calls for the acoustic treatments to be applied at the listener's end of the room, while leaving the speaker end (relatively) untreated. Try this and see if it helps. If not, then you will probably have to do a much more sophisticated analysis using a good test disk -- such as the one that Rives sells at his Web site. |
