Detailed Speaker Setup and Optimization

[pjwd]

I don’t think anyone is disputing the science of room acoustics. Sound can be reflected, transmitted, absorbed or diffracted (diffused). Absorbers will absorb the sound wave above its cutoff frequency. I think was some are sying is that they work too well. There is no dispute (at least I don’t think there is) that absorbers reduce the amount of energy in a room. That’s what they do.

If RT60 is a measure of the sound energy in a room then some people will like it lower or higher than others. As I mentioned, a typical living room with carpet on the floor and curtains, sofa, chairs, etc. has an RT60 of about 0.5. To me that is manageable. I oersonally like a little lower at 0.4. It is clear that Amir likes it higher and wants a livlier sound.

All Amir and I and a few others are trying to communicate is that there are “special” spots in the room where the sound coming from the speaker is having minimal interaction with the room as perceived from the listening position.

Why would it be difficult to believe that there exist special spots. These types of things exist all over physics. E.g. the Lagrange point where the Webb telescope is parked. This is how I think about it. Imagine the energy or pressure in the room (produced by a speaker) as a scalar field. That energy surface is going to have maxima and minima. That surface is going to change as the sound source moves. There is going to be positions that will minimize the variation. There will be positions where the listening seat is sitting in a low spot or high spot and everywhere in between. When we find that special spot and speaker attitude the “rooms effect” on the sound gets much quieter.

Of course there are the best spots for everything .. I hope you don't think I am arguing with that proposition..room modes are ruthless!
I was pointing out to Ron why I believe people have been disappointed with the various after market devices available.
Equally, after the best spot is found there is no reason not to take the science further and look at how the sound develops in the space and introduce devices that further enhance clarity without losing liveliness and engagement.. it's a continuoum.
Phil

 

[sbo6]

Hello Ron,
please read my post again, what I say is the key for right audio judgment is our ears not objective measurements. Audio measurement tools for flat frequency response in room and using room treatment for absorbing reflections are ok if finally we get good sound but the problem is room treatments as you think are not good for sound.
My experience is similar to experts (like David @ddk, Romy the Cat , Kevin Living Voice) they do not use heavily room treatments like others (Robert Harley, Mike, You …).

objective solutions like room treatments, dsp room correction are similar objective solutions for designing amplifiers. As you know high feedback complex solidstate amplifiers have perfect measurements but the sound is awful.

I have paid for many acoustic panels but finally I removed all of them.

What you omitted which is very important is, in general, it very much depends on the size of your room. The bigger the room, the less treatment is needed.

Also, both your ears AND audio measurements matter and should be used to complement each other for best results.

 

[bonzo75]

Romy the Cat stole the writing of a Russian guy and changed its wording and meaning where it fitted him,

I wasn’t aware he stole it. Interesting trivia

 

[adyc]

I don’t think anyone is disputing the science of room acoustics. Sound can be reflected, transmitted, absorbed or diffracted (diffused). Absorbers will absorb the sound wave above its cutoff frequency. I think was some are sying is that they work too well. There is no dispute (at least I don’t think there is) that absorbers reduce the amount of energy in a room. That’s what they do.

If RT60 is a measure of the sound energy in a room then some people will like it lower or higher than others. As I mentioned, a typical living room with carpet on the floor and curtains, sofa, chairs, etc. has an RT60 of about 0.5. To me that is manageable. I oersonally like a little lower at 0.4. It is clear that Amir likes it higher and wants a livlier sound.

All Amir and I and a few others are trying to communicate is that there are “special” spots in the room where the sound coming from the speaker is having minimal interaction with the room as perceived from the listening position.

Why would it be difficult to believe that there exist special spots. These types of things exist all over physics. E.g. the Lagrange point where the Webb telescope is parked. This is how I think about it. Imagine the energy or pressure in the room (produced by a speaker) as a scalar field. That energy surface is going to have maxima and minima. That surface is going to change as the sound source moves. There is going to be positions that will minimize the variation. There will be positions where the listening seat is sitting in a low spot or high spot and everywhere in between. When we find that special spot and speaker attitude the “rooms effect” on the sound gets much quieter.

The problem is these special spots are not only function of the dimensions of the room. These spots depend on walls, floors and ceiling materials. They also depend on furnishings. Having appropriate room treatments can widen these spots. Also for high ceilings, it is not enough just to have carpet to reduce RT60 as the floor and ceiling bounces take longer to travel. Personally, I prefer to hang diffusers than paintings on the wall. These diffusers are more pleasing to look at.

 

[Amir]

I don’t think anyone is disputing the science of room acoustics. Sound can be reflected, transmitted, absorbed or diffracted (diffused). Absorbers will absorb the sound wave above its cutoff frequency. I think was some are sying is that they work too well. There is no dispute (at least I don’t think there is) that absorbers reduce the amount of energy in a room. That’s what they do.

If RT60 is a measure of the sound energy in a room then some people will like it lower or higher than others. As I mentioned, a typical living room with carpet on the floor and curtains, sofa, chairs, etc. has an RT60 of about 0.5. To me that is manageable. I oersonally like a little lower at 0.4. It is clear that Amir likes it higher and wants a livlier sound.

All Amir and I and a few others are trying to communicate is that there are “special” spots in the room where the sound coming from the speaker is having minimal interaction with the room as perceived from the listening position.

Why would it be difficult to believe that there exist special spots. These types of things exist all over physics. E.g. the Lagrange point where the Webb telescope is parked. This is how I think about it. Imagine the energy or pressure in the room (produced by a speaker) as a scalar field. That energy surface is going to have maxima and minima. That surface is going to change as the sound source moves. There is going to be positions that will minimize the variation. There will be positions where the listening seat is sitting in a low spot or high spot and everywhere in between. When we find that special spot and speaker attitude the “rooms effect” on the sound gets much quieter.

Thank you Todd

https://www.whatsbestforum.com/threads/my-personal-experience-with-detailed-speaker-setup-im-finally-there.38069/

 

[pjwd]

What you omitted which is very important is, in general, it very much depends on the size of your room. The bigger the room, the less treatment is needed.

Also, both your ears AND audio measurements matter and should be used to complement each other for best results.

Until you have cathedral like 6 sec reverb
Every space has to be dealt with as needed.. no doubt larger rooms make it easier .. I don't think anyone on this forum would not know that.... but they do have longer reverb times but advantageously less early refletions .. each case on its merits

 

[Tonari]

In my experience, it's quite possible to deal with medium and high frequencies. In some cases, carpets, curtains, ordinary furniture can do it. I could almost always confirm these changes in the room with the RT60 and other measurements, but again, this applies to mid and high frequencies.
I found bass management to be the biggest challenge. I'd like speaker placement to be enough to handle the low-frequency modes in the room, but I doubt it. Either you're lucky with your room (size, shape, wall material,...), or you have to opt for bass traps to attenuate resonances.
That's the conclusion I've drawn so far. I'm not saying it's a universal rule. All this discussion helps me to nuance my opinion.

 

[sbnx]

Romy the Cat stole the writing of a Russian guy and changed its wording and meaning where it fitted him,

Any ideas on who this Russian guy is/was? Where did he write stuff down? In a book or blog or ???

 

[sbnx]

The problem is these special spots are not only function of the dimensions of the room. These spots depend on walls, floors and ceiling materials. They also depend on furnishings. Having appropriate room treatments can widen these spots. Also for high ceilings, it is not enough just to have carpet to reduce RT60 as the floor and ceiling bounces take longer to travel. Personally, I prefer to hang diffusers than paintings on the wall. These diffusers are more pleasing to look at.

Agree. The "spots" depend on everything. Change something and the spot changes.

 

[Lagonda]

A. Polakow, he wrote that he had written something similar himself that had gotten deleted and used this guys writing, with his own changes instead .

Any ideas on who this Russian guy is/was? Where did he write stuff down? In a book or blog or ???

http://goodsoundclub.com/Forums/ShowPost.aspx?PageIndex=1&postID=994#994

 

[Mike Lavigne]

Mike,
1- You never had any experience about DPOLS so you can not understand what happen to sound when speakers are in perfect position.

over the years i have read about DPoLS a few times on Romy's site. you are not the first person to reference it. and.....as he targets me from time to time as we had a relationship back in the day, i get notice about it sometimes. and i agree generally about the thinking behind it. to a degree, i go down that road myself. i won't argue how far or how much i pay attention to it in that exact form. but there is plenty of positive ideas from it.

speaker positioning is a critical issue, and i've spent plenty of time on it moving my speakers in micro amounts. i will say that since i last did those micro adjustments, 8 years ago, i have made zero changes to my room tune and system preamp and amplifier. it continues to deliver for me.

2- after speaker placement you can start lowering RT by some changes in room.

My ears are sensitive to dynamic and energy of music so I never liked acoustic panels.

everything in a room is part of the acoustics. everything. i would agree that absorptive panels are best avoided. but rooms and speakers are all different, and you should use the best tools to reach your musical goals. but you can't fix a bad room with band aids. and a good room does not need much.

not all listeners are interested in extended deep bass, but some are. so that does change things a bit. it's a factor in how systems are approached.

large dynamic speakers act differently than horns or panels. and the greater the expectations for large scale music the more the room has to be right.

as experts told before the key for good sound in room is speaker placement not using huge amount of room treatments.

not sure we agree on the expert thing, but i agree that speaker placement should be the main thing, but every situation is different. small room acoustics is not that narrow a case.

 

[Tangram]

At the risk of stating the obvious, it’s worth remembering we do not want to introduce additional reverb in our listening rooms. The reverb is already on the recording. It doesn’t need a boost. But we also don’t want to kill the reverb that’s on the recording either. Hence the judicious, not excessive use of treatments.

 

[Elliot G.]

Are you trying to make the music on a recording sound like its in a hall or are you trying to produce the sound on the recording which may or not be in a hall? The first is a coloration the second is trying for accuracy.

There are two very different skill sets at work here. One is the ability to place and set up the speakers and the system and tune it.
The second is controlling the reflections and issues within the playback space or room acoustics.

These are not the same thing and in many/most cases are not the same person.

 

[mtemur]

Are you trying to make the music on a recording sound like its in a hall or are you trying to produce the sound on the recording which may or not be in a hall? The first is a coloration the second is trying for accuracy.

There are two very different skill sets at work here. One is the ability to place and set up the speakers and the system and tune it.
The second is controlling the reflections and issues within the playback space or room acoustics.

These are not the same thing and in many/most cases are not the same person.

And key to this accuracy you described as producing the sound on the recording is comparing same tracks with a pair of headphones every once in awhile. That’s my opinion.

There are very few stereo recordings, mostly dual channel mono and some of the stage depth, dimension etc are added by room reflections as you described as hall effect.

 

[mtemur]

I see here a lot of dogma against absorption panels on the criticism that they operate on all frequencies as opposed to just problem frequencies. Have these partisans measured the frequency response of their random living room furnishings to assure themselves that those random furnishings target only problem frequencies?

The response is likely "well, my random living room furnishings result in an overall sound I'm happy with, so I don't have any problem frequencies to target." But that's disingenuous because it ignores the fact that if you started with an empty room you probably wouldn't be happy with its overly reflective sound. So whether you fill the room with organic furnishings or commercial products is simply personal aesthetic preference.

I think you’re missing the point between synthetic room treatments and furnishings made from organic or natural materials. It is not about which is more effective. I’m sure room treatments are more effective even though they also operate on other than target frequencies. The problem (or my problem) with synthetic room treatments is their sound signature. They correct some problematic frequencies but turn every instrument sounding like they’re made out of sponge, thin and un-involving. Suck the life out like chemotherapy. That’s what I think.

 

[Mike Lavigne]

I think you’re missing the point between synthetic room treatments and furnishings made from organic or natural materials. It is not about which is more effective. I’m sure room treatments are more effective even though they also operate on other than target frequencies. The problem (or my problem) with synthetic room treatments is their sound signature. They correct some problematic frequencies but turn every instrument sounding like they’re made out of sponge, thin and un-involving. Suck the life out like chemotherapy. That’s what I think.

i think playing the furniture/fixture/clutter acoustic lottery is no more or less successful than actual added treatments with some sort of plan. i will agree that the room might be likely a nicer more agreeable place to listen with the home furnishings, windows as windows, and keep the significant other more satisfied. which then somehow makes the sound better too. in those cases hard to be aware of what we don't know.....how good it might be if we went the other way and got serious about the space and little things in the room? the whole because of, or in spite of, thing.

and some driver types and sizes are more or less room dependent. that can be a factor.

the bigger question is whether a space is multi-use or a dedicated listening room. where sound does take the priority. speakers can be where they need to be, listening position can be where it needs to be. stuff out of the way. we have all seen pictures or been in semi-hoarder spots where the sound happens to be heavenly. or it's just a mess. and sometimes it depends of the expectations for deep bass or not. and expectations for truly large scale music reproduction. those who have those as a marginal concern are in a different spot that those who place a high priority on it.

YMMV.

 

[wil]

I think you’re missing the point between synthetic room treatments and furnishings made from organic or natural materials. It is not about which is more effective. I’m sure room treatments are more effective even though they also operate on other than target frequencies. The problem (or my problem) with synthetic room treatments is their sound signature. They correct some problematic frequencies but turn every instrument sounding like they’re made out of sponge, thin and un-involving. Suck the life out like chemotherapy. That’s what I think.

You’re categorizing professional room treatments vs typical room furnishings as Synthetic vs Organic?

Rockwool, commonly used in many professional treatments, is an organic material. Many couches and chairs for instance use synthetic materials.

 

[mtemur]

You’re categorizing professional room treatments vs typical room furnishings as Synthetic vs Organic?

Rockwool, commonly used in many professional treatments, is an organic material. Many couches and chairs for instance use synthetic materials.

Rockwool is mainly used behind drywalls. Do you suggest it’s widely used inside room without any cover? BTW any furnishing made from synthetic material is equally bad IMO.

 

[Ron Resnick]

I think you’re missing the point between synthetic room treatments and furnishings made from organic or natural materials. It is not about which is more effective. I’m sure room treatments are more effective even though they also operate on other than target frequencies. The problem (or my problem) with synthetic room treatments is their sound signature. They correct some problematic frequencies but turn every instrument sounding like they’re made out of sponge, thin and un-involving. Suck the life out like chemotherapy. That’s what I think.

Do you think the sound waves can tell the difference, and that they behave differently, whether they are bouncing off polyester on a couch versus polyester on an acoustic panel?

PS: Presently I am using acoustic panels only to absorb first reflections in the middle of the side walls. The other wall surfaces are three-quarter inch solid walnut, which is an organic material.

 

[andromedaaudio]

Sound Waves can be trained.
But only by experienced listeners .( for a fee)