The argument for/against room treatment

[Ron Resnick]

I had professionals treating my room rendering it dead and bass heavy . . .

Why did they do this?

 

[morricab]

After reading a lot of the posts here saying its essential or it isnt to have your room treated, I honestly think you guys are looking at this backwards.

What do I mean? Let’s do a little thought experiment. Do you think that treating your room will make the sound in that room sound more real? If you were to replace your stereo in your untreated room with live musicians what do you think you would hear? You would hear all the same issues with room modes, reflections, decay times etc. that you heard with your stereo; however, it would still be unmistakably live and you would likely never confuse this with your own stereo... even if you made a recording on the spot and played it right back...you would still hear some degree of artificiallity that gives the game away.

What this means is that room treatment is NOT a means to greater realism in reproduction. It would act on a live performance in that same room in the same way (or at least very similar way) probably improving both in the process but not closing the gap between them.

What then is room treatment good for? Well, for difficult rooms it can definitely make the sound quality more enjoyable (probably make conversation in that room more pleasant too). Rooms that already have good acoustics (like I am blessed with) Wouk only benefit minimally from treatment and as I said above it doesn’t close the realism gap. If you have a difficult room, by all means treat it to get a more listenable sound but don’t think you are making things more real.

On the subject of experts, on has to be extremely careful as to what the person you are hiring as an expert is really expert at. I am an expert in a particular area of science (I have a PhD in Analytical Chemistry and am a leading expert on Aerosol Science and measurement) and got that way not through just years of experience “doing” it but was formally trained at Universities and have published about 40 papers in various peer reviewed journals. If someone comes to me on this or a closely related topic they can be quite sure they will get good advice. In other fields of science I know a lot but it is not definitive and I would always qualify what I think I know.

In any field with a strong subjective component, be VERY wary of so-called experts.

You should beware any hifi dealer who claims to be an expert because they have Blah, blah years in the industry...they have no more or less expertise than audiophiles who have had the hobby for a long time...many of them sell poor sounding products, which immediately disqualifies in my view as they demonstrate the experience then is for nothing because they can’t hear what’s wrong with what they sell. They are mostly trying to sell you what they think they can sell.

As to acoustics experts, you have to beware to what they are trying to modify your room to. If they do primarily studios, they will likely make your room way too dead because when all you have is a hammer, everything looks like a nail. They will be able to hit a target room pretty accurately...this is the science part of what they do and this is perfectly fine; however, do they know WHAT target they should hit with your room to truly improve it? I suspect many, if not most, do not as they are probably not really audiophiles themselves.

Electronics and speaker designers in audio may or may not be formally trained engineers but in such a subjective field as audio, it is more important that the damn guy(or girl) can actually hear what their creation does in a relatively unbiased way.

 

[Duke LeJeune]

When I "hatch" my future stereo I will start with no room treatment at all (except for carpet on the rear two-thirds of the room). I will not automatically absorb the points of first reflections, or fill the corners with ASC Tube Traps.

The first experiment will be the points of first reflections.

In my opinion, how the loudspeaker interacts with your room (in particular what the speaker is doing off-axis) is a significant piece of the puzzle. In other words "room treatment" is NOT a one-size-fits-all thing! I like your methodical approach, and I like your starting point(s).

Let’s do a little thought experiment... If you were to replace your stereo in your untreated room with live musicians what do you think you would hear?

Imo this is an extremely useful thought experiment. An environment which sounds good with live instruments would also sound good with speakers that do a good job of reproducing live instruments. The net result would be a very enjoyable "they are here" presentation. (And peering through the other end of the telescope, one might argue that the speakers should sound good in a room where live instruments would sound good.)

Imo there is a more elusive goal which might be worth pursuing, which is a "you are there" presentation. Achieving a "you are there" presentation implies that the venue ambience/envelopment/immersion cues which are on the recording DOMINATE over the playback room's "small room signature" cues. Imo thoughtful room treatment can play a role in that.

 

[Audiophile Bill]

In my opinion, how the loudspeaker interacts with your room (in particular what the speaker is doing off-axis) is a significant piece of the puzzle. In other words "room treatment" is NOT a one-size-fits-all thing! I like your methodical approach, and I like your starting point(s).



Imo this is an extremely useful thought experiment. An environment which sounds good with live instruments would also sound good with speakers that do a good job of reproducing live instruments. The net result would be a very enjoyable "they are here" presentation. (And peering through the other end of the telescope, one might argue that the speakers should sound good in a room where live instruments would sound good.)

Imo there is a more elusive goal which might be worth pursuing, which is a "you are there" presentation. Achieving a "you are there" presentation implies that the venue ambience/envelopment/immersion cues which are on the recording DOMINATE over the playback room's "small room signature" cues. Imo thoughtful room treatment can play a role in that.

Totally agree especially your last paragraph. My own view is that if your listening room would sound good with live musicians in it, then it is actually likely a bad room for the pursuit of ultimate audio replay. Most acoustics for acoustic musicians (particularly classical) tend to be much more live with enough natural reverb. This acoustic merely camouflages and hides any recording acoustic / ambience.

 

[Duke LeJeune]

My own view is that if your listening room would sound good with live musicians in it, then it is actually likely a bad room for the pursuit of ultimate audio replay. Most acoustics for acoustic musicians (particularly classical) tend to be much more live with enough natural reverb. This acoustic merely camouflages and hides any recording acoustic / ambience.

You can think of the in-room reflections as the CARRIERS for the venue cues on the recording, in particular the reverberation tails, as these should be presented from all around rather than from only two discrete locations (the left and right loudspeakers, as would be the case in an overdamped room). So the in-room reflections do good things as well as bad things! But not all in-room reflections are equally beneficial, nor equally detrimental.

The KEY lies in the ARRIVAL TIME of the reflections (assuming they are spectrally correct, or nearly so, to begin with).

The earliest reflections are the ones which most strongly present the playback room's undesirable "small room signature" cues, and are also the ones which degrade clarity the most.

The later reflections are the ones which most effectively present the reverberation tails on the recording, which convey the recording venue's acoustic space (whether said "acoustic space" be real or engineered or both). As long as they aren't TOO loud clarity is preserved.

So imo it's not a matter of reflections being good or bad - it's a matter of minimizing the bad ones while encouraging and cultivating the good ones. Imo the loudspeaker design itself can play a significant role here... you ever try horns???

;^)

 

[Solypsa]

Here we see the actual science is not how to control sound waves per se but how do we comprehend sound waves. ( saying nothing new here ... )

Late reflections carry similar info to sound waves experienced directly- if anything the reflected info is somewhat compromised. However that info ( even if not identical to direct input ) is VERY important to how we comprehend music.

I suspect if this topic were *important enough* ( meaning financially lucrative ) a better metric would be available. But we must remember that realistic musical replay is actually not that important anymore. ( imho )

 

[pjwd]

The earliest reflections are the ones which most strongly present the playback room's undesirable "small room signature" cues, and are also the ones which degrade clarity the most.

The later reflections are the ones which most effectively present the reverberation tails on the recording, which convey the recording venue's acoustic space (whether said "acoustic space" be real or engineered or both). As long as they aren't TOO loud clarity is preserved.

What Duke said !
Ignoring dispersion pattern of speakers ( which I understand is how you are going to control room reflections) I would say there are very few rooms that would not benefit from judicious, targeted, minimalist treatment and a good, independent, experienced engineer who will follow a clients brief should be able to implement exactly that.
Unfortunately those engineers are a rare breed !
To fully reap the benefits the best starting point is an acoustically sealed room ( below 30dB ambient ) Then the effect of treatments becomes very clear and you could find that in a room open to the house some treatments would produce limited gains as they are obscured by ambient noise and are not worth pursuing on aesthetic vs benefit scale

It is very hard to generalize in this area.
On live music I am pretty sure no one is envisioning Led Zeppelin in their room - more like a string quartet or folk singer which will sound fine in most spaces and very good in a well designed listening room.
On recording spaces the variety is enormous , from super dead spaces and music constructed in the mixing to large halls and natural ambience ( although that is usually goosed a bit as well ) I am sure we all have favourites from all of these origins
etc....etc...

Do you think that treating your room will make the sound in that room sound more real?

Real sound - a good name for a thread !

 

[sbnx]

It is very hard to generalize in this area.
On live music I am pretty sure no one is envisioning Led Zeppelin in their room - more like a string quartet or folk singer

I don’t know about others but i am pretty close to having Rush in my room. Playing something like “Tom Sawyer” at realistic levels is a memorex moment.

much harder to believe a full symphony is in your room. Although once i set my sysyem up to sound like i was on the mezzanine at the Meyerson. Great for symphonic music but other genre’s suffered..

 

[spiritofmusic]

Sbnx, I'm impressed if Neil Peart is channeling into your room from The Great Unknown.

 

[pjwd]

I don’t know about others but i am pretty close to having Rush in my room. Playing something like “Tom Sawyer” at realistic levels is a memorex moment.

much harder to believe a full symphony is in your room. Although once i set my sysyem up to sound like i was on the mezzanine at the Meyerson. Great for symphonic music but other genre’s suffered..

I was referring to the points made in previous posts about actual musicians in the room vs your stereo and what that meant re acoustics - I see from your previous posts you are into all of this so no surprise you get a good result !

I have always wanted to attend the Meyerson hall - as I recall they have large chambers around the perimeter of the hall that they can open up and change the hall volume therefore extend reverb time - that is a next level approach !

Presume you are a local ?

Phil

 

[dcathro]

I had my studio in London professionally sound proofed by Recording Architecture, and the acoustics by Nick Whitaker.

Since moving to Australia, 15 years ago, and having a normal home listening environment, I have been experimenting with sound isolation and acoustics. Some of what I have learned is:

- a sealed environment is advantageous to keeping the energy within the room.
- a regular rectangular shaped room is better than having a very irregular shaped room with alcoves or adjoining rooms.
- open plan is a disaster
- there needs to be the right amount of absorption in the room to control the RT
- the absorption has to be placed in the optimum positions - putting it in the wrong place is as bad as having none or too much. Even many acoustic engineers get this wrong.

 

[adyc]

To me, room treatment includes materials of wall, floor and ceiling. For two rooms which one has wooden floor, wooden wall and the other room has marble floor and concrete wall will sound very different even if they are the same size. Just like guitars made of different hardwoods will also sound different. If my room has too much window, I try to cover them with wooden blind. Adding a sofa in the room is also room treatment. So everything in your room is room treatment.

 

[sbnx]

Sbnx, I'm impressed if Neil Peart is channeling into your room from The Great Unknown.

Yeah, i can see Neil back there beating the crap out of that drum kit with his laser precision. He was an awesome drummer.

 

[sbnx]

I was referring to the points made in previous posts about actual musicians in the room vs your stereo and what that meant re acoustics - I see from your previous posts you are into all of this so no surprise you get a good result !

I have always wanted to attend the Meyerson hall - as I recall they have large chambers around the perimeter of the hall that they can open up and change the hall volume therefore extend reverb time - that is a next level approach !

Presume you are a local ?

Phil

Yes, i live in a suburb of Dallas. The acoustics in the Meyerson are very good. I used to be a season ticket holder for the Dallas Wind Symphony.

 

[Kal Rubinson]

it's a matter of minimizing the bad ones while encouraging and cultivating the good ones.

Good advice for much of life.

 

[morricab]

In my opinion, how the loudspeaker interacts with your room (in particular what the speaker is doing off-axis) is a significant piece of the puzzle. In other words "room treatment" is NOT a one-size-fits-all thing! I like your methodical approach, and I like your starting point(s).



Imo this is an extremely useful thought experiment. An environment which sounds good with live instruments would also sound good with speakers that do a good job of reproducing live instruments. The net result would be a very enjoyable "they are here" presentation. (And peering through the other end of the telescope, one might argue that the speakers should sound good in a room where live instruments would sound good.)

Imo there is a more elusive goal which might be worth pursuing, which is a "you are there" presentation. Achieving a "you are there" presentation implies that the venue ambience/envelopment/immersion cues which are on the recording DOMINATE over the playback room's "small room signature" cues. Imo thoughtful room treatment can play a role in that.

Hi Duke, you sidestepped a bit from my original point, which was that treating the room will not make a stereo system sound more real. It is still easy to distinguish live from reproduced both before and after treating a room. No gain in that perspective has been made with room treatment. It can, possibly if done right, make music (and speech for that matter) more enjoyable and so for that reason I am not anti-treatment...use as needed for max enjoyment of music. However, I think you are right that a room that is sonically good for live will also be sonically good for a stereo system.

As to the “you are there” perspective, well you will never get rid of your own room sound unless you make it very dead and then I think most would agree the sound is no longer pleasant. So, you will always have an overlay of your own room acoustics with the recorded acoustics...it’s unavoidable IMO. That doesn’t mean you can’t perceive the recorded space far from it...it’s just that it won’t be purely what’s on the recording. The room has to pretty bad to destroy this IME.

Would improvements in the room this way enhance realism? Are you better able to suspend disbelief ? Again you can for sure improve the listening experience by making things clearer and less muddled and hearing the decay of the recorded space. However, I am of the mind that most big works recordings are too limited to allow brief one is actually hearing the real thing that you won’t get there anyway. It is why I tend to favor small scale works in evaluating realism... it is actually possible to get a believable solo instrument or perhaps up to quartet size. I don’t have a real answer on this one, so I will give it a think but my immediate response is that if Your system gets the ”they are here” right it should do very well on the “ you are there” but due to limitations of the media, big works will never sound real.

 

[morricab]

You can think of the in-room reflections as the CARRIERS for the venue cues on the recording, in particular the reverberation tails, as these should be presented from all around rather than from only two discrete locations (the left and right loudspeakers, as would be the case in an overdamped room). So the in-room reflections do good things as well as bad things! But not all in-room reflections are equally beneficial, nor equally detrimental.

The KEY lies in the ARRIVAL TIME of the reflections (assuming they are spectrally correct, or nearly so, to begin with).

The earliest reflections are the ones which most strongly present the playback room's undesirable "small room signature" cues, and are also the ones which degrade clarity the most.

The later reflections are the ones which most effectively present the reverberation tails on the recording, which convey the recording venue's acoustic space (whether said "acoustic space" be real or engineered or both). As long as they aren't TOO loud clarity is preserved.

So imo it's not a matter of reflections being good or bad - it's a matter of minimizing the bad ones while encouraging and cultivating the good ones. Imo the loudspeaker design itself can play a significant role here... you ever try horns???

;^)

All very good technical advice... the art is to execute these suggestions that gives a really good sonic outcome.

Directionality of horns definitely helps a problematic room from my experience. I had my stuck in a pretty small room for quite awhile...and it really worked! People were always very surprised by that setup as it flew in the face of what they “knew”.

 

[morricab]

To me, room treatment includes materials of wall, floor and ceiling. For two rooms which one has wooden floor, wooden wall and the other room has marble floor and concrete wall will sound very different even if they are the same size. Just like guitars made of different hardwoods will also sound different. If my room has too much window, I try to cover them with wooden blind. Adding a sofa in the room is also room treatment. So everything in your room is room treatment.

Wood is good... my ceiling is all wood and sloped at around a 30 degree angle from 3 meters at the speaker end to around 7 meters high at the opposite end.

 

[Audiophile Bill]

Wood is good... my ceiling is all wood and sloped at around a 30 degree angle from 3 meters at the speaker end to around 7 meters high at the opposite end.

Roof conical bass horn is being requested by the horn gods, Brad. Make it happen they say

 

[morricab]

Roof conical bass horn is being requested by the horn gods, Brad. Make it happen they say

I can just take imagine my wife’s expression when a huge bass horn magically appears on the ceiling