[Eric D]

By this formula, a line source would reach -60db in 524 KILOMETERS!!

First things first, the geek in me is going "COOL!".  

But to get serious, please understand you're talking a 20 hz wave generated by a line source that should be on the order or 100 km long, right?  Once you get to distances where the line source appears to be a point (where you can see the two end points), the sound starts to obey the inverse square law.  

Talking large-scale atmospheric sounds, are you saying that instead a thunder clap (which one reference I found says is 110 dB) dies out in 36 meters by attenuation alone, let alone the inverse square law?  I suggest the lightening bolt as an excellent line noise source we can find in nature, and that it's line source nature is one of the reasons we hear it over a great distance.  

It seems as though you are stuck on the assumption that lower frequencies take a significantly longer time to decay

From absorption, yes.  Let me return to the thunder clap, and suggest that when we are close to it that we hear a wider range of frequencies, but that as we get further away, the HF is attenuated, we hear a low rumble.

If you were in an open field, you would have to use -6db, but add back for the ground to about -4.5db, that would put us at around 40 feet. At 40 feet in an open field, you have to raise your voice considerably to speak to someone.

I can see my mistake was staying in the ideal world and hoping that the numbers would seem real to you.  Let's try to be more "real world."  [rolls up sleeves]  

I'll buy that -4.5 dB on an open surface. (I've seen -4dB too, but close enough).  So let me also get away from the ideal world and use a rural ambient noise level of 30 dB and a whisper volume of 20 dB

Using your attenuation value and voice level of 70 dB, you're saying someone can't pick your voice out of the background at  10 meters.  Spotting you 5dB in voice level, I'm saying that my 65 dB voice (that's not on the quiet end of conversation) becomes about as intelligible as a whisper at that range, and that it disappears into background at about 50 meters.  I'm willing to suggest that anyone who wants to personally test the validity of those models actually go stand in a field and try it.

wacky figures ...  remove assumptions and rebuild the theories from the ground up...   am aware that I am challenging the theories of echo and reverberation, and perhaps even sound propogation as a whole...

Well, I'm wondering why you're questioning everything else, but keeping the -3dB attenuation number.   And I worry when someone starts to believe that 3 intersecting pieces of drywall can actually amplify energy, rather than talking about resonance and directing or focusing waves.   So I wonder which specific theories you're talking about, and what tests have been done that disprove them.  I don't see that your treatments call into question the wave theory I've been discussing.   I think it's theoretical basis is more in our perception of sound and what's important.  

As John C. suggested (but I'm trying not to get into that side of this thread), there are different goals to treating a room which are incompatible, but all valid, and perhaps of different importance to different people.  I really, sincerely, like your new Adapt line.  I don't know what direction I'm going with my combo family-room, HT, listening room - I'm waiting until  I do a good set of measurements and it's a long-term fiddle-about project anyway.  But they will absolutely be one option I consider.

I only brought up my disagreement in hopes that, if I'm at all more correct, that it might help keep you from going down dead-end paths or even possibly suggest to your inventive mind other possibilities.   Maybe you'll have some new products I'll also be interested in down the line.

respectfully,

[edited out incorrect use of "sotto voce"]

[csero]

Whatever it is caused by, the decay is proportionately higher, and I believe that Ethan has some measurements on his website that confirm this as well.  Resonances are easy to see on a waterfall plot.

Proportional means no ringing, no resonance...

[ctviggen]

You hear a low rumble from a thunder clap because the ground transmits low frequencies better than high.  Or, put another way, low frequencies go through the ground better than they do the air.

[Eric D]

You hear a low rumble from a thunder clap because the ground transmits low frequencies better than high.  Or, put another way, low frequencies go through the ground better than they do the air.

Could you please refer me to a source for that statement.  (not that lf goes through the ground better than they do the air, but that that's the reason that lightning's rumble is xmitted by the ground).  

Off hand, I'd expect any discussion to get into things like reflection, refraction, and angles of incidence you know.  Unless we're rejecting all that too...

Thanks,

[8thnerve]

Whatever it is caused by, the decay is proportionately higher, and I believe that Ethan has some measurements on his website that confirm this as well.  Resonances are easy to see on a waterfall plot.

Proportional means no ringing, no resonance...

Yes, please pardon my semantic error.  Consider it changed to "significantly".
 

[ctviggen]

I guess I'm wrong:

http://www.islandnet.com/~see/weather/elements/thunder2.htm

Nonetheless, I think what happens with lightening is completely inapplicable to what happens to sound in a closed room.

[8thnerve]

Talking large-scale atmospheric sounds, are you saying that instead a thunder clap (which one reference I found says is 110 dB) dies out in 36 meters by attenuation alone, let alone the inverse square law? I suggest the lightening bolt as an excellent line noise source we can find in nature, and that it's line source nature is one of the reasons we hear it over a great distance.

No of course not.  Again, atmospheric calculations do not apply directly to in room behaviors.  And discussing theories about thunder is hardly germaine to our discussion of sound within a room.  And they are theories no matter where they come from.  Facts are simply theories that most people believe. (eg, the world is flat, the sun rotates around the earth, etc.)

I'm saying that my 65 dB voice (that's not on the quiet end of conversation) becomes about as intelligible as a whisper at that range, and that it disappears into background at about 50 meters.

Seriously?  Your normal talking voice in an open field dissapears into the background at over half the length of a football field?  I would disagree with you there, but what difference does it make?  We are still talking about sound outside which is not of relevance to us here.  No experimentation supports your claim that the RT-60 of a low bass note lasts significantly longer than a treble note.  All your figures would produce an RT-60 of over several minutes for low bass, and we know that that simply doesn't occur.  And no amount of furniture or other absorptive materials that we use would stop such a wave, which incidentally is the hardest to absorb.  If this were true, the entire bass spectrum would be a  mode, not just the room modes.  We know on a waterfall plot that the bass lasts a little bit longer on average than the treble frequencies, and we know that it is because high frequencies are easier to absorb, and some get absorbed along the way.

You don't believe my reasons for why sound behaves the way it does.  That's no big deal, and it isn't the first, nor will it be the last time that this occurs.  Using your arguments, which are being misapplied in regards to atmospheric versus architectural acoustics, can give no explanation as to why my products would have any effect on the sound within a room at all.  Current room acoustics theories also do not give an explanation for these product's results.  I am not unwilling to consider them; it's that I already have and they simply do not tell the whole picture, and I truly believe many of them to be simply incorrect.  I am not just trying to be different.  Based on my research, I simply don't believe that the reasons that current acoustic science applies to the observations are correct.  I think I have been pretty clear about what I do believe is happening and bringing up formulas and calculators from sites all over the internet based on theories I have already disagreed with will not result in any new information.  

I will continue to compile my research and eventually will have it organized enough to submit for peer review.  And if it is rejected I will continue to refine and submit it and hopefully at some point it will be published and considered with the rest of accepted acoustic theories.  Either way, it is of little consequence to me.  If I can continue to make products that help people achieve better sound, have fun with the science and enjoy my life with my wife and daughter, I'll be just fine.  I just don't understand why you are interested in googling every claim I make and try to find a site that claims otherwise.  None of them will agree because it is original research.

[John Casler]

John Casler wrote
When I read this statement, I immediately thought about an anechoic chamber which is great for measuring frequency response. That aside, most feel that the sound in an anechoic environment is unrealistic and unpleasant. Every time you go to a concert, sound reflection is part of the equation. Hang a bunch of foam on the walls, and you will start to create a dead room, without a lot of high frequency. John, if that is your preference so be it. Regardless, it is the opposite of my preferenc ...

Hi JCC,

First off, my suggestions about sound "reproduction" do not reflect on the quality, design, or effectiveness of the Eighth Nerve Product you are using.

While they, from my understanding, are slightly reflective they still are the beginining to "subtracting" room interactions.  In fact, their effectiveness is based on removing the most damaging of interactions.

I need to make that clear since sometimes, if there is disagreement on a principle or two, the perception is one of being negative about a product or its function, and that is not the case.

Secondly, your statement that "most most feel that the sound in an anechoic environment is unrealistic and unpleasant", may be true, but is is based on absolutley "NO" critical listening experience.

Anyone who has ever walked into a "real" anechoic chamber will attest that is is somewhat erie, to "not hear" the room or any of your surroundings.  It is akin to walking into a totally dark room where you can see absolutly nothing.

Your comparison of reproducing a concert "in your room" and "going to a concert", is where most get sidetracked.

The "acoustic needs" of a Concert Venue, are far different than the acosutic needs of a home reproduction system.

At the original venue, you actually "use the room" to help distribute the sound as evenly and with the minimum amount of distortion.  The original venue is also not focused on a "sweet spot", since the idea is to make each "seat in the house" a good one.

In a venue, generally the speakers are usually "high dispersion horns" and spread all over the stage.

Also if the concert is being recorded to be reproduced at home, the recording (if done well) will "contain" the ambient backround sounds that form the sound of the venue.

In the home system, because the sound is reproduced from 2 speakers, it will have a limited listening postition (sweet spot) where balance soundstage and imaging will form.  

Additionally, if you then take the ambiance that is already on the recording, and "mix" it with an overwhelming set of ambient sounds from your reproduction environment, the original set is sonically overwhelmed and the accuracy I spoke of is reduced.

It is akin to setting a Big Screen in the forest and playing a video of Bambi.  While the environment around the screen might seem to add to the film, it isn't accurate to the orignal.

The point being, a home system and a venue are very different in some of their requirements and set up.

Second point being "any" sound from the room that overpowers the original signal is damaging.

And the "third point" which you brought up which is very important is "preference".  The most important part of listening is what you like when you hear it.  Accurate or not, it it sounds good to you at this point in your system, it is a good thing.  

Having a clearer cell phone conversation is also a bonus  

[Eric]

John,

Are you recommending no room treatments, or another solution entirely?

[John Casler]

John,

Are you recommending no room treatments, or another solution entirely?

Hi Eric,

For me personally, I think room treaments need be approached on a proportional scheme based on the rest of your system performance.

I am "always" experimenting, but my goal would be defined as making the room boundaries acoustically tranparent.

This would allow the summation of stereo signal from each speaker to more accuratley convey what the microphones picked up at the venue, without adding in reflected distorting or damaging sonics from the room.

It is important to note that when I speak of this it is relative to 2 channel audio only.

I also acknowledge the weaknesses Frank discusses in the reproduction of stereo, as well as the futility of assuming we will ever acheive a "twin" of the original.

However, I find that effective treatments offer more accuracy and quality to the listening experience.

So yes, I advocate using the combination of treatments that help you acheive the sound you like. (or that your wife will let you get away with)

[PhilNYC]

And the "third point" which you brought up which is very important is "preference". The most important part of listening is what you like when you hear it. Accurate or not, it it sounds good to you at this point in your system, it is a good thing.  ...

An interesting story...I was visiting an audiophile friend (a reviewer, actually) who invited me over to hear some new speakers he was reviewing.  He was raving about them, which definitely had my interest piqued, because his reference speakers were pretty serious (Kharma Ceramique 2.2) and I've always been very impressed with his system.  I arrived at his place, and he sat me down in the sweetspot.  Said "listen to this!" and put on a CD...and almost immediately I got one of those "skunky beer" looks on my face.  Not bad in the midrange and highs, but the bass was thumpy due to a low frequency resonance in the room.  Now this reviewer has historically been one of the most detail-oriented people I've known in terms of fine-tuning his room treatments...admittedly, he goes to lengths with some fairly controversial products in his room...but I have never heard his room come even close to this kind of resonance.  It wasn't huge, but to me it was definitely a noticeable annoyance.

So he asks "what do you think?"  And I told him exactly what I thought.  And he looks at me and says "hmmm...but don't you hear how these speakers excite the energy in the room?  I've never heard a speaker do that like these do.  I think it's really fantastic."

Anyways, suffice it to say we had a very long discussion, and we're still communicating about it...apparently its been such a long time that he has heard his system with any kind of resonance issues, and he found himself liking the "enveloping sound" that the resonance gave him.

So...yes, I agree.  Personal preference is in the end the ultimate judge for how you should go about treating your room...

[John Casler]

An interesting story...I was visiting an audiophile friend (a reviewer, actually) who invited me over to hear some new speakers he was reviewing.  He was raving about them, which definitely had my interest piqued, because his reference speakers were pretty serious (Kharma Ceramique 2.2) and I've always been very impressed with his system.  I arrived at his place, and he sat me down in the sweetspot.  Said "listen to this!" and put on a CD...and almost immediately I got one of those "skunky beer" looks on my ...

Great Story Phil, and it reminds me of one on my side.

Not to long ago, I had the pleasure to meet the fellow who was the set up man, for one of if not the most "famous" reviewer in the World.

I won't mention names but even his initials (HP) are equally well known.

Well to make a long story short, he had set up this system ($19K Hornings) that he was raving about and I was not quite "skunk faced" . but was certainly not impressed.

Later I prefered to ask him about his set up exploits rather than discuss how I felt the sound we just heard rated.  

When asked what type, model or brand of acoustic treatment he used when setting up for this reviered reviewer, he looked kind of bewildered, shrugged his shoulders and said he seldom used any  and when he did he didn't notice any difference.    

[Eric D]

I just don't understand why you are interested in googling every claim I make and try to find a site that claims otherwise. None of them will agree because it is original research.

I apologize.  I pointedly did not "google every claim" you made nor did I go to any question of room interactions and the final resulting room acoustics thjeories.  My reason for referring to outside sources was to try to find some common ground to discuss, not in any way to try to find sites that "claim other" than you.  

Facts are simply theories that most people believe. (eg, the world is flat, the sun rotates around the earth, etc.)

Interesting statement...  Without resorting to a dictionary, googled or otherwise, I would assert that facts are things we directly observe, and that theories are tested hypotheses that allow us to successfully make predictions.

Please note that I am NOT questioning your theories of room interaction/acoustics.  I am admittedly questioning two of the underpinnings that you put forth.  My purpose in doing so is to suggest other paths you might pursue if you should happen to run into observations/facts which you can't resolve with your theory sometime in the future - no more, no less.

My writing was only in response to your calculations of "atmospheric" response, not to the room problem.  You are the one brought up the behaviour of sound over an uninterrupted length - it's what prompted me to write.

The laws of physics dictate that in a cylinder, a fully reinforced environment where sound can travel in only one direction without expanding, sound decays at a rate of 3db per meter. In free space sound decays at a rate of 6db per meter.

You weren't talking the behaviour of the room, you were discussing the propagation of sound through air when constrained to only one dimension.   Anyway, this was and is the first thing I'm questioning.   I posited that you had possibly confused it with the inverse square law for free field and inverse law for a two-dimensional spreading, in both cases of which, the quoted reduction is for each doubling of the distance rather than per meter.   I further believe that the confusing wording of cylinder led to confusion about wave propagation in one dimension, which has no spreading loss, and doesn't decay due to spreading but only by absorption.

The second was and is the value of -3dB/meter for the absorption rate, which I speculate was arrived at by someone (not saying you) through that confusion with cylindrical spreading.  It just seemed high to me.

But back to testing hypotheses to arrive at theories that allow us to make predictions.  Using my sets of hypotheses, I predict "as intelligible as a whisper" at about 10 meters, and "disappears into background at about 50 meters."  When I correct for the real world, wouldn't your hypotheses lead us to predict "as intelligible as a whisper at about 5 meters and "disappearing into background" at about 10 meters?  This is the test I suggested to consider which of our competing "theories" of atmospheric absorption rate is correct.

Again, atmospheric calculations do not apply directly to in room behaviors

That value for absorption by air IS important, in the open, in a room, or otherwise.  Or are we saying the air in a room is that manifestly different than the air outside when it comes to transmitting sound? [and I almost cut this last piece as it may tread too close to your room acoustics theories, but I offer it for what it's worth:]  If we were in a room 10 meters apart, by your calculations we wouldn't be able to hear each other at all.  The direct signal would be absorbed, and all reflected paths are longer.

bringing up formulas and calculators from sites all over the internet based on theories I have already disagreed with will not result in any new information.

Whoops - I conjecture that you are probably tired of me, so probably best to go away now...   Anyway, it's not likely but if I ever run into you at some show, etc.  I'd love to buy you a beer or other libation of your choice, then run out into a large field and yell at each other (like idiots, I'm sure each of our wives would agree ).  And at the end of it, I'd declare you a fine gentleman.  

Thanks for the civilized discussion, and best of both skill and luck in your future endeavors.

Extremely Sincerely,

[csero]

This would allow the summation of stereo signal from each speaker to more accuratley convey what the microphones picked up at the venue, without adding in reflected distorting or damaging sonics from the room...

You know, the (only) ideal hi-fi mic setup is the sereo mic pair at the best seat of the house. The only problem is that nobody, i mean NOBODY is using it, because it is not stereo palyback compatible. Just think about this.

[John Casler]

This would allow the summation of stereo signal from each speaker to more accuratley convey what the microphones picked up at the venue, without adding in reflected distorting or damaging sonics from the room...

You know, the (only) ideal hi-fi mic setup is the sereo mic pair at the best seat of the house. The only problem is that nobody, i mean NOBODY is using it, because it is not stereo palyback compatible. Just think about this.

Hi Frank,

That might be 100% true, and I only say "might" because I have not heard a recording produced that way, so I can't speak with experience.

Conceptually I agree.

On second thought I might have heard a "demonstration" of one of those mikes on a Stereophile Test CD (#3 I think)

The futility of audio, is sometimes quite frustrating, but even in less than perfect production, if care is taken in the reproduction, incredible things can be heard.

[csero]

Hi Frank,
On second thought I might have heard a "demonstration" of one of those mikes on a Stereophile Test CD (#3 I think)

Even on those demo cds the mic pair placed much closer than the normal listening distance would be.

[8thnerve]

If we were in a room 10 meters apart, by your calculations we wouldn't be able to hear each other at all. The direct signal would be absorbed, and all reflected paths are longer.

That's the thing; if we were in a room, the corners would be amplifying the sound giving us not only the ability to clearly hear each other, but to have a decay rate (RT-60) that with this size would probably be around 1.5 seconds.  That is the entire point that I am trying to make, that the corners are what are responsible for the measurements that we get in a room.  How else could you explain an RT-60 time going from 1 second to 0.45 seconds with only the application of my products, that have NO exposed absorptive material?

I appreciate your discussion, and truly bear you no ill will.  I am just expressing frustration as I am unable to discuss your points, as I disagree with the basis of the theories behind them or their applicability to the current situation.  And regarding fact versus theory, we observe results, not the reasons.  Our reasoning is theory, even if most people believe it.  Everyone believed that the world was flat because everyone looked around and could see that it was a fact, however the fact was that the world looked flat due to it's size.  Everyone could see for a fact that the Sun rotated around the earth.  The real fact was that the Sun moved in relationship with the earth.  All of our acoustics theories are observed results which we then apply a set of reasons to that we believe to be the most accurate and explanatory method to describe these results.

I must however return to my cave as many customers are waiting for recommendations, placement drawings, and a response!

Best Regards,

Nathan Loyer
Eighth Nerve

[Eric D]

Just one parting thought:  

Thanks for your time.

[8thnerve]

Just one parting thought:  

Thanks for your time.

Thanks for your discussion.  I am sorry I am unable to get to the grit that you would like to here, but I will take you up on your libation offer, and we can discuss this in further detail if we have a chance to meet.  Perhaps CES next January?

Best Regards,

Nathan Loyer
Eighth Nerve

[John Casler]

 John ,

I appreciate your response, but your style of "conversation" is not entirely innocent. For instance:

John Casler wrote:
Are you saying that "mixing" reflected room sonics "adds" accuracy?

This is not something I ever said, nor implied. Saying things in this way is a rhetorical device used to accuse someone of making a statement which is obviously incorrect, and therefore results in challenging the questioned speaker's credibilility. Whether you do this coinsciously or not is not of much interest to me, but it isn't appropriate in the course of actual productive conversation. If you don't understand what I am saying, then simply ask for clarification. Other people read this than just us, and it can be confusing and overwhelming. Let's not try and undermine the clarity of this discussion by speaker for each other. Speaking for ourselves will get us in plenty of trouble by itself.  

Nathan, you said that absoption "attenuated" HF.

I said it doesn't attenuate what you hear "directly from the speaker".

If it doesn't come from the speaker, and isn't attenuated by treatment, reflected sound is "mixed" with the direct sound.

I simply wanted to know if you felt that there was some way, reflected sound mixed with direct sound is accurate?

It is difficult for me to see that it does, but I have had people who I respect, tell me that the backwave from a dipole speaker makes a signal more accurate (which I still don't beleive and certainly cannot hear)

In light of that dipolar supposition, I was questioning your "concept/theory" to see if it added anything to the puzzle.

Personally I can't find any way to reconcile that reflected waves can "improve accuracy of performance" within a room, unless very rigid measurments were taken, and set up was precise, and even then I have my doubts.

JohnCasler wrote:
The Bose 901 was based on the "clear physics" you (I think) are referring to. It is how much reflected sound we might hear in our everyday natural environment, in the real world.


No, it is not. The Bose 901 is a poorly designed dipolar speaker. That is it. It is in no way relevant to what I am talking about, and frankly, I am flabbergasted that we continue to discuss this. We are listening to the reflections of the original sound wave created by the speakers whether it comes out of one driver, 8 drivers, 3 drivers pointing front and 3 pointing back, or any other combination. The differences caused by these designs simply produces a different set of reflections. I am not saying that this is what we want to listen to or what god wants us to listen to or anything else regarding theory or recording versus playback, etc. I am saying that we cannot discern the difference between the first wave that hits us and the subsequent hundreds of reflections that reach our ears at almost the same level within a few hundredths of a second, period.

I'm not saying that you don't hear what you consider to be an improvement when you put up a lot of absorbtive material, I am saying that it is not for the reasons that you believe it is.
   

Amar Bose was a brilliant man who recognized what you are (or seem) to be saying, and that is we hear much more reflected sound than direct.

That is what I was refering to.  The Bose 901's were designed to use his observations in the listening room.

Of course it was not what most of us would use now for various reasons.

I continue to express that your goal to hear only the "direct" sound is an interesting and idealized fascination. There has never been a person who has ever heard only the "direct wave" of any sound. Even when sound travels through our ear canal it causes reflections. Every surface causes reflections to a certain extent, these refelctions happen incredibly fast, and our brain integrates them all into a whole. The ratio of direct to reflected sound that we hear is for all practical purposes 0:1. Your experimentations that tell you that when you put up absorptive material to absorb reflections that you hear more of the direct sound than before are simplified and inaccurate conclusions to a complex set of results.

   

I find the ear canal references mocking and don't think they need addressing since no one ever thought I was refering to direct injection to the auditory (8th) nerve.

I agree however that reducing room interaction is an idealized fascination, as is High Performance Audio all together.

I am open to less simplified and accurate explanations to my set of results.

It seems rather straight forward.  Reduce room interaction = improved ability to sense signal.

Let me make my point very clear: putting absorptive surfaces in a room does not improve your ability to hear the direct sound wave by any statistically significant amount. We hear the summation of the direct wave and the multitude of reflections. Reducing the level of these reflections simply results in a percieved wave that measures lower in the areas that were reduced, not some grand uncovering of the original wave  

I would respectfully disagree.  

The "perceived" wave as you call it might "measure" less, but is not perceived as less.

Your HF attenuation is a good example.  I take it you are measuring a test tone at the listening position and "summing" both direct and reflected HF info.

But this does not mean that the ear/brain combo would find the HF info less, if we "subtract" the "reflected" HF's added.

Maybe this example will help explain.

Let say you are sitting in a lighted room.  At one end of the room facing you is a wall with a pinhole in it, with light coming through it.

But because the room is lit, (by basically reflected light) you cannot even see this pinhole.

Now turn out the lights.  In 60 seconds (after your eyes adjust) the pinhole becomes a "beacon".  The detail of that pinhole is now "very" perceptible and it is something you would have totally missed, if you didn't get rid of most of that extra light.

Now if you were measuring "light" at the listening position, more would have been measured with the lights on, but is you are measuring perception of the pinhole of light (aka "detail") the perception was greatest with the lights out.

Reducing room interaction is quite similar.  Removing levels of the reflected sound, improves perception of detail, dynamics and other characteristics such as tone, impact, and decay.

The reason you think that it does from your listening, is that the reduction of the high frequency energy eliminates the lowest level harmonics, which increases the perceived ratio of fundamentals to the noise floor. This allows you to pick out more of the individual sounds because the spurious ambient information (that otherwise would be distorted due to the corners) has been reduced. Please don't respond back to this with all the attributes you get with your setup. You have made that very clear. This is my explanation for why you percieve the benefits you claim. You are more than welcome to disagree, but there is no point in reiterating why you believe otherwise. I am acknowledging that for you.
   

I think the point is "not why" it does what it does, but that it "DOES what it does".  Who doesn't want more detail, dynamics and all the rest?  Who doesn't want to hear the venue's "real" ambiance (if it is in the recording)?

While there may be a more "technical" explanation, and even formulas, the relevance is in the result, not the explanation.

In wrapping this up, my post are basically to share the sonic experiences, and increase the awarness of what various levels of acoustic treatments can offer to the more serious listener.

Much of what I have been able to try is not available to the average enthusiast, without a dedicated room and a lot of imagination/creativity.

And I again still sugest treating in stages based on room problems, and think that the Eighth Nerve products are an excellent starting point along with Ethan Winers Bass Treatments.

We can't all agree on everything, except we know what we like, when we hear it.