The argument for/against room treatment

[Bobvin]

When Bonnie engineered my remodel, she included in her modeling some recent research where the amount of treatment needed before a change was ”heard” was studied. Somewhere I have the link, but to my recollection a room was used where every wall (in individual portions) could be changed to a flat surface, a diffusive surface, or an absorptive surface. I seem to remember not until ~ 2/3 of the room was “treated” did listeners detect much difference. I am summarizing a research study, and probably poorly.

Ultimately, my walls include custom BAD panels, and I have of course heard pros and cons to BAD panels. Commercials ones i have seen (RPG) seem to vary the number and spacing of “holes” but I had not seen varying the size of the holes. In my application there are different drillings in an area ~ 18” centered on ear height when seated.


My room sounded pretty damn good before we remodeled but not when volume increased > ~ 90db. Then the rooms problems caused the sound to become “confused” just too much uncontrolled energy. Things improved greatly after remodeling and bass tonality, impact, and depth vastly improved.

Random room treatment is trial and error. Even an engineered solution may not get you the results you hope for (sadly many examples of this.) Every room is unique.

 

[stehno]

Well depends on what you consider room treatment. As an example a well stuffed sofa and a heavy rug acts as room treatment. It helps damp and absorb portions of the frequency spectrum. So some may say they don't use room treatment when in actuality they are and don't realize it. When you say room treatment some automatically jump to dedicated absorbers and diffusers and skip over furnishings.

Others have already stated and acknowleded this in previous posts so I don't think you'll much of an argument here.

When you listen to live music you also hear room reflections from the performance space. I really enjoy headphones for the convenience of taking music with me where ever I go. I prefer speakers though for listening at home.

Live music traveling and merging and melding and interacting with the recording hall's acoustics and boundaries is a very big part of the live performance and very much desired in the concert hall and during playback in the listening room. Much of this ambient info is captured by the recoridng mics and embedded in many recordings. If and it is so, why do you find this same concept (hearing the acoustics and/or reflections of a listening room) appealing during playback? I can only think of one, no 2 reasons why you might.

This is a very complex issue

Doesn't have to be.

and you can get really good sound by using furnishings

Can you provide examples of really good sound? Can you also provide examples of furnishings used to achieve this really good sound?

and speaker placement on their own without resorting to expensive room treatments.

Agreed. But speaker placement is a topic unto itself which for the most part and to the best of my knowledge is all about pursuing a superior / musical bass which if achieved will impact most/all parts of the playback presentation.

I also think it can be done without "room correction".

Agreed. Well, hang on. What exactly are you speaking of that can be done without room correction? And how can it (whatever it is) be accomplished?

It also depends on you room. Some are really good others down right suck. If you are lucky to have a good room you are more than halfway there and makes good results with minimal treatment a lot easier.

Rob

You seem to lack specificity. What is it exactly that depends on your room? What in your opinion constitutes a good room and a room that sucks? How does one determine whether or not the room itself is good?

 

[Robh3606]

Hello Stheno

I suggest you read Floyd Tooles book on Sound Reproduction. He explains it much better than I could hope too.

As far as headphones it is my personal preference. They just don't do it for me.

Rob

 

[spiritofmusic]

I've had three main pivots in my interest in audio.
One was being seduced by the convenience of CD in 1983 only to be wrenched back to LP five years later by an amazing Linn Sondek LP12/Naim/active Linn Isobarik demo before the decade was out (although I have pivoted a bit back to digital, now somewhat genre agnostic);
then, my proposed move to stats/powerhouse SS sabotaged by my epiphany on tubes in mid-2000s as a Hovland HP200 tube preamp seduced me with sheer magical sonics and swung me twds the practicality of high efficiency spkrs in a large room via tube liquidity;
and finally, my sheer lack of awareness that my old room was poor sonically, unknowingly accepting sub par sound across the board, punctured by the very same system a year later being transformed in a new acoustic.

Fascinatingly I thought I had cracked the acoustics puzzle in one £40k step (the cost of creating this room) just by having a better sounding room, but good friend Barry (Blue58) on visiting here highlighted aspects of imaging and phasiness that he felt needed addressing, and on his advice I reintroduced GIK absorber panels on front and side walls which definitely enhanced coherency. Again, I was late to the party on picking up this was needed.

In the last 6 weeks, I've been working hard at bedding in and optimising install of my new SOTA Condor Eclipse Roadrunner tt motor system/Farad LPS. Major uptick all around, except for some harshness on a significant minority of my less stellar prog rock LPs.

I had been in contact w Phil (PJWD on this forum), and I finally made good on his suggestion to address my eaves reflections (my room is in an attic space, 18x55, w 30° descending eaves R & L) by install of ten PET boards in the reflections zone. And I'll be damned, they've contributed a whole lot to a warmer sound but no detriment on speed or texture of my sonics, just win/win of further reduced deletrious boundaries reflections, specifically here, my eaves.

My final frontier on room treatments is to go further w these PET boards, seven on each side wall in first and second reflection points, eight across midline of front wall, and additionally make up some custom 1200x600x600 corner bass traps utilising high absorption polyester acoustic wool.

I've gone from, not so much a skeptic on acoustics, more totally oblivious, to a full convert, and finding this is an area that keeps rewarding persistence.

 

[DaveC]

I think speaker type, position and orientation in the room play a much more important role than has discussed here so far.

Duke covered this just a couple posts before. It's the main reason Toole/Harman think having smooth off-axis response is top priority. IMO the polar map is the best way to visualize this...

Speaker directivity / off axis response: theory and measurement techniques

This blog article is the first in a mini-series about speaker directivity or off axis frequency response. For us the two most important things in determining sound quality in a home theater or stereo are the speaker and the room. Above the room’s transition frequency the speaker’s directivity...

www.acousticfrontiers.com

It also explains why people have varying opinions besides the fact people have different preferences. In the link below you can find measurements of some speakers that will show how much variability there is. IMO, people are much more likely to enjoy reflections if they are "spectrally correct" vs having significantly different spectral content vs the direct sound, I agree w/ Duke's explanation of this as well.

The 3D3A Lab at Princeton University

www.princeton.edu

I think there is also a very wide range of personal preferences. One person's "live and exciting" is another's muddled mess and vice versa.

 

[PeterA]

I think there is also a very wide range of personal preferences. One person's "live and exciting" is another's muddled mess and vice versa.

I agree with this Dave. And then there is also one’s perception of how close what he is hearing resembles what his memory is of the live event. On the other side of a muddled mess is an overly detailed sound with super black backgrounds and pinpoint imaging which sounds great and can be very enjoyable, but it’s not necessarily what everyone hears when listening to live acoustic music.

I think the important thing is to know what you want and to try to achieve that within your limitations.

 

[DaveC]

I agree with this Dave. And then there is also one’s perception of how close what he is hearing resembles what his memory is of the live event. On the other side of a muddled mess is an overly detailed sound with super black backgrounds and pinpoint imaging which sounds great and can be very enjoyable, but it’s not necessarily what everyone hears when listening to live acoustic music.

I think the important thing is to know what you want and to try to achieve that within your limitations.

I recently heard a system that is "super black" and "pinpoint" to a degree I didn't know was even possible. While imaging was precise, there was no soundstage to speak of so it was a total "they are here" experience. Vocals had a convincing clarity to them and seemed detailed, but spatial cues were strangely absent. Not sure what to think about it TBH, my entire goal is a "you are there" experience... OTOH, I want to keep editorializing to a minimum and hear what the artists intended. But, I do have a changed view of how far a system can go towards "pinpoint", that's for sure!

 

[Robh3606]

I recently heard a system that is "super black" and "pinpoint" to a degree I didn't know was even possible. While imaging was precise, there was no soundstage to speak of so it was a total "they are here" experience. Vocals had a convincing clarity to them and seemed detailed, but spatial cues were strangely absent. Not sure what to think about it TBH, my entire goal is a "you are there" experience... OTOH, I want to keep editorializing to a minimum and hear what the artists intended. But, I do have a changed view of how far a system can go towards "pinpoint", that's for sure!

I find this to be very recording dependent. I think a well set-up system should be able to accurately convey what is recorded. On recordings with good spatial clues that is what we should hear and conversely same with the lack. Ideally our systems should change character depending on the source material so they should be all over the map just like recordings are.

Rob

 

[DaveC]

I find this to be very recording dependent. I think a well set-up system should be able to accurately convey what is recorded. On recordings with good spatial clues that is what we should hear and conversely same with the lack. Ideally our systems should change character depending on the source material so they should be all over the map just like recordings are.

Rob

Agreed! This is why I prioritize a "you are there" presentation... where you are should be recording-dependent.

 

[PeterA]

I recently heard a system that is "super black" and "pinpoint" to a degree I didn't know was even possible. While imaging was precise, there was no soundstage to speak of so it was a total "they are here" experience. Vocals had a convincing clarity to them and seemed detailed, but spatial cues were strangely absent. Not sure what to think about it TBH, my entire goal is a "you are there" experience... OTOH, I want to keep editorializing to a minimum and hear what the artists intended. But, I do have a changed view of how far a system can go towards "pinpoint", that's for sure!

Dave, Coincidentally I was reading another thread about a vintage speaker and I came across this quote from the review in Stereophile:

Conclusion
You read about speakers that perfectly image but have limited bass, or hyperdetailed speakers that, over time, fatigue the listener. But the Bozak Concert Grand does everything well while not excelling at any one sonic parameter. I believe this is its greatest strength. It is dynamic beyond belief, with gobs of musical detail and harmonic richness. A pair of them are magical in their ability to deliver space and ambience cues, but they image more like what you hear at a concert—not "pinpoint" imaging, but a more blended sound. And the speaker has extraordinary but not superfast bass. The Bozak Concert Grand is the most musically satisfying loudspeaker I've heard. It may be the best non-horn vintage speaker you can own.”

I appreciate the reference to live music and how one does not hear pinpoint imaging in a live music setting. So why would we try to achieve this (and super black backgrounds for instance) from our systems unless it was simply because we like the effect of these audiophile attributes?

 

[DaveC]

Dave, Coincidentally I was reading another thread about a vintage speaker and I came across this quote from the review in Stereophile:

Conclusion
You read about speakers that perfectly image but have limited bass, or hyperdetailed speakers that, over time, fatigue the listener. But the Bozak Concert Grand does everything well while not excelling at any one sonic parameter. I believe this is its greatest strength. It is dynamic beyond belief, with gobs of musical detail and harmonic richness. A pair of them are magical in their ability to deliver space and ambience cues, but they image more like what you hear at a concert—not "pinpoint" imaging, but a more blended sound. And the speaker has extraordinary but not superfast bass. The Bozak Concert Grand is the most musically satisfying loudspeaker I've heard. It may be the best non-horn vintage speaker you can own.”

I appreciate the reference to live music and how one does not hear pinpoint imaging in a live music setting. So why would we try to achieve this (and super black backgrounds for instance) from our systems unless it was simply because we like the effect of these audiophile attributes?

I try to recreate what's on the recording, and as Rob just said, the measure of this is the ability of the system to allow recordings to sound distinct from one another with as little "editorializing" as possible.

So, if the recording does have pinpoint imaging, then that's what the system should reproduce. Your idea that a system should always sound like live music is simply on the opposite end of the spectrum from those who always want a pinpoint image and a black background.

Like most things, I believe it's best to avoid the extremes and once again...I allow the recording to dictate how my system sounds to the greatest extent possible. It seems you have the wrong idea about me and how my system sounds. I DO NOT attempt to achieve a "super-black" background or "pinpoint imaging" regardless of the recording, but I don't see any problem with it if that's what the owner wants. Just like I don't agree with trying to make a system sound like live music regardless of the recording, but I don't see a problem with it either, if that's what you like.

 

[PeterA]

I try to recreate what's on the recording, and as Rob just said, the measure of this is the ability of the system to allow recordings to sound distinct from one another with as little "editorializing" as possible.

So, if the recording does have pinpoint imaging, then that's what the system should reproduce. Your idea that a system should always sound like live music is simply on the opposite end of the spectrum from those who always want a pinpoint image and a black background.

Like most things, I believe it's best to avoid the extremes and once again...I allow the recording to dictate how my system sounds to the greatest extent possible. It seems you have the wrong idea about me and how my system sounds. I DO NOT attempt to achieve a "super-black" background or "pinpoint imaging" regardless of the recording, but I don't see any problem with it if that's what the owner wants. Just like I don't agree with trying to make a system sound like live music regardless of the recording, but I don't see a problem with it either, if that's what you like.

I see. I thought you were describing a system you heard recently that always sounded as though it had pinpoint imaging and black background.

I agree with you that would not portray what is on the recording. By the same token I don’t think a system should always sound like live music if the recording is preventing it from doing so.

I have heard components that create a sense of enhanced detail, black backgrounds, and pinpoint imaging when inserted into a system. And I am not advocating that. In my system room acoustic treatments did overlay a sonic character to all recordings, and I grew to not appreciate that.

 

[DaveC]

I thought you were describing a system you heard recently that always sounded as though it had pinpoint imaging and black background.

I was, but I'm not putting it out there as an example to follow and I have no idea why someone would want to achieve this kind of presentation. I stated I heard such a system because I was previously unaware that this kind of sound was even possible, and now I have a better idea about what you're referring to.

 

[sbnx]

Dave, Coincidentally I was reading another thread about a vintage speaker and I came across this quote from the review in Stereophile:

Conclusion
You read about speakers that perfectly image but have limited bass, or hyperdetailed speakers that, over time, fatigue the listener. But the Bozak Concert Grand does everything well while not excelling at any one sonic parameter. I believe this is its greatest strength. It is dynamic beyond belief, with gobs of musical detail and harmonic richness. A pair of them are magical in their ability to deliver space and ambience cues, but they image more like what you hear at a concert—not "pinpoint" imaging, but a more blended sound. And the speaker has extraordinary but not superfast bass. The Bozak Concert Grand is the most musically satisfying loudspeaker I've heard. It may be the best non-horn vintage speaker you can own.”

I appreciate the reference to live music and how one does not hear pinpoint imaging in a live music setting. So why would we try to achieve this (and super black backgrounds for instance) from our systems unless it was simply because we like the effect of these audiophile attributes?

I agree with this. A good stereo setup can produce aural images that are far more detailed and precise than we hear at any live event. Even if you sit a few rows back, dead center at an event (large or small) you just have a general sense of where the performers are.

 

[spiritofmusic]

A few years back I posted that I never heard specific imaging at a live classical concert, only to be told in no uncertain terms that many can pick out instruments HERE, and RIGHT HERE, and THERE, and OVER THERE. That whole layers of instruments could be visualized. So, what's the consensus on that, and how it affects our requirements from home audio?

 

[Al M.]

A pair of them are magical in their ability to deliver space and ambience cues, but they image more like what you hear at a concert—not "pinpoint" imaging, but a more blended sound. And the speaker has extraordinary but not superfast bass. The Bozak Concert Grand is the most musically satisfying loudspeaker I've heard. It may be the best non-horn vintage speaker you can own.”

I appreciate the reference to live music and how one does not hear pinpoint imaging in a live music setting. So why would we try to achieve this (and super black backgrounds for instance) from our systems unless it was simply because we like the effect of these audiophile attributes?

It's great when a system is magical in its ability to deliver space and ambience cues, but the question is always how much is real. The question is how much is actually on the recording, and how much of that information is artificially amplified by the room.

Previously the many windows in my room were exposed (didn't matter if with blinders down or not) and I had a less absorbing carpet in the area from speakers to front wall; the speaker drivers are 7 feet from the front wall. Every recording had "spatial cues", which translated to spatial depth. Also music that should sound upfront sounded spatially recessed, to the point of absolute annoyance -- at least for me personally. Some audiophiles visiting were impressed by all this "depth", but I just hated it.

Reflections in my room actually amplified and exaggerated recorded "space" as it was reproduced. And yes, in some cases the effect was "magical" (I will never again hear "Sweet Caroline" by Neil Diamond with the same magic as I did then), but it was beyond belief; I don't think it was real.

Now with ASC window plugs and a more absorbing carpet the differences from upfront to spatially recessed, spatially deep presentation are maximized, and so are differences in general spatial ambience. There seems to be reproduced what is actually on the recording, and not more.

So when I hear that there's so much magical space and ambience information from a system, my skepticism shoots up, and I ask myself how much is real and how much is exaggerated, either by the room or by non-linearities in the system itself.

In this case, "more information" is not necessarily always better.

 

[spiritofmusic]

Al, I can tell you the simple purchase of £50 acoustic Rockwool stuffed into the 12 cub ft hatch interconnecting my 7000 cu ft space to to the 21,000 cub ft main chapel space below, created a small miracle. Shored up imaging, almost like having a centre speaker, smoothed out my whole room bass response. And yes, result was more, but not artificially more, space and ambience. Vocals image better, and have way greater inteligibility, while maintaining a natural ability to be grounded and float. As if the chest is reproduced more strongly, but overtones rise unimpeded. All in all, way greater realism of substance and air.

 

[Al M.]

To put it another way: previously in my room the effect was a bit like putting all the music through a reverb circuit.

Sure, that adds something that wasn't there before, but that extra "information" isn't real, it's an added artifact.

 

[spiritofmusic]

For me, every step on acoustics has been a real voyage of discovery, from jumping into the deep end with how much improved my system could sound in a different room, to subtle but welcome uptick of GIK panels, to crazy improvements from eliminating a major bass suck out, to reducing harshness with eaves treatments.

Still more to do, critically to get way better corner bass traps, and improved front and side wall treatments.

Handy having a dedicated room, none of these treatments would look at all acceptable in a mixed use living/audio space

 

[pjwd]

I agree with this. A good stereo setup can produce aural images that are far more detailed and precise than we hear at any live event. Even if you sit a few rows back, dead center at an event (large or small) you just have a general sense of where the performers are.

However if you hear chamber music in a chambre ,as i am sure many of us have , you do get that precise image that a well done recording can deliver in playback
You get a lot of direct sound with diminished room ambience sitting close in a small venue as opposed to a 600 or more seat hall
If the small room is sound isolated you also get a black blackground
I enjoy precise imaging even though you rarely have the privilege of hearing it live

Phil