[audiojerry]

I think you guys don't seem to get it, ANYTHING your room does to the sound is wrong, the goal is to make it completely go away. If your system sounds wrong in a totally acoustically dead room, there is something badly wrong with the system.

Frank Van Alstine

This post came from http://www.audiocircle.com/index.php?topic=5710&start=0

Bill or Nathan, care to offer your views on this?

[Rob Babcock]

Definately do read the whole post first, though.

[8thnerve]

Bill or Nathan, care to offer your views on this?

I promise I will, once I have a spare moment!

Nathan

[Carlman]

Was that quote from the 'anechoic chamber' debate?  I can tell you that the goal for me with room treatments is to subdue the effects of my room enough to where the recording has a chance at recreating a space for itself.  

That's what 8th Nerve products did for me.  A dead room sucks the life out of music for me.  An anechoic chamber is eery and very difficult to produce for home use.  To each his own but, I'd rather use my room instead of completely defeat it.

[audiojerry]

Frank's quote came from the AVA forum thread titled, "Questions on 550ex".

No disrespect intended to Frank or AVA. I've heard his gear, and I was very impressed. No way would I challenge him on his amp design talents or his skill in voicing his amps to be musical, but it seems like he believes he is equally skilled at knowing the best way to design a listening room, and I would challenge him on some of his statements related to that.    

It might be a matter of semantics. His definition of an acoustically "dead" room may not at all be the same as an "anechoic chamber". I have to wonder if Frank has ever been in one. It's scary, because when you are in one, you can hear your heart beating and your blood pulsing through your arteries. In the thread, he described his way of treating a room with acoustic wall fabric, and then adding acoustic ceiling tiles if necessary. I don't think either of these techniques will produce anything approaching anechoic or even acoustically dead. I think it could result in a quiet room, but I'm sure there would be nodes at certain frequencies where it would not measure flat.  
Carlman wrote:

I can tell you that the goal for me with room treatments is to subdue the effects of my room enough to where the recording has a chance at recreating a space for itself.

I believe that this is probably more of what 8th Nerve would hope to achieve, without killing slam and dynamics.

I believe my room is too acoustically dead, and it is not good for the music, but without removing insulation from behind walls and ceiling, and removing acoustic ceiling tiles, I'm SOL.

[nathanm]

Ripping the scabs off old wounds are we Jerry?  Heh heh!  

The term "acoustically dead" has a very negative connotation.  To me it's more semantics - like I would use the term "peaceful and quiet" to describe the same type of room.  I think Jerry's basement is very peaceful and quiet, which I feel is a good thing.  Wether or not it is also "acoustically dead" well, I dunno.  I'd would say a hand clap in a "dead" room would have absolutely NO reverb tail on it whatsoever, whereas even a "peaceful and quiet" room might have just enough ring to it that indicates the size\sonic character of the space.

You don't even need speakers in there to determine what kind of sound you might get.  If it's a big open space with large windows, hardwood flors etc.  you'd expect to get a big wide open sound, perhaps with some ill-favored reflections upon critical listening.  In a smaller room with carpeting, lower ceilings, lots of stuff on the walls you might get a much more quiet, intimate sound.  Pretty much walking into a space and hearing your own or other people's voices gives you instant feedback as to what you will get when you stick your speakers in there.  Even completely non-acoustic factors are going to color your perception of the sound.  I guess it's one of those "Feng Shui" things perhaps. Ha!

I doubt there's a danger of anyone making their room anechoic, as it would be physically and financially unfeasible.  Personally I like "dead" rooms, but then again I don't feel they really live up to that term anyway.

[Rob Babcock]

We could go on and on and put words in their mouths, and I don't want to do that.  But my feeling from the thread wasn't that he claimed cloth alone could render a room completely anechoic, and I'm not completely sure Frank would want that.  I imagine AVA & 8th Nerve will probably clarify and discuss this as time permits.

I agree with Mr. Van Alstine that if you ask a record producer how much of the sound of your listening room he wants in his recording the answer will be "none."  Or very little.

Isn't that essentially what Big B does my making his speakers more directional?  That's also the belief of Bill Duddleston (of Legacy)- more direct sound reaching your ears vs more reflected is better.

As for my own feelings, I've never been in a room I felt was too dead.  Almost every room I've ever "heard" had more reverberation and slap echo than I'd want.

[audiojerry]

Nathan, that was very nicely said, and adds another perspective on the subject. I agree that you can pretty much predict how a room will work for audio without having an audio system turned on.

Just for the record, "acoustically dead" are not my words, they are Frank's: "If your system sounds wrong in a totally acoustically dead room, there is something badly wrong with the system."    

A listening room could be viewed similarly to the acoustics of symphony concert halls. The best venues are not acoustically dead spaces. They have the right amount of liveliness, which is not accomplished by accident. Getting the acoustics right is a science that requires a high degree of training. Very few of us can afford to start from scratch and build a listening room intended solely for audio. I've had the privelge to enjoy music in such a room, and it was memorable. The room was "tuneable" with adjustable knobs on the walls and floors that changed the amount of tension between studs and joists. This room was far from being "acoustically dead". Perhaps peaceful and quiet, but a muted slap echo was definitely audible. Imaging was precise, and the soundstage was nothing short of glorious.  I'd take this room in a heartbeat over my much quieter room.

[Rob Babcock]

Maybe he meant "totally acoustically dead" as in an anechoic chamber.  Maybe not.  That's the problem with written communication vs speaking; you're words are permanent.  I hope he responds to this.

Still, some will come down on the side of "dead" over live.  I agree with NathanM, I don't like that term.  I haven't listened to music in an anechoic chamber, but it would be interesting.  I definately prefer a drier acoustic than some I guess.  Let the reflections/ambience come from my recordings (especially the MC ones) not my room.

Of course, the best situation for producing music and reproducing music aren't always the same.

BTW, there's an acoustically amazing hall in my city, and it's a joy to hear music there.  Cantus recorded their last album there.

[SWG255]

I have a friend who has taken much time to treat his listening room, which also doubles as a home recording studio. After all his research and DIY building of bass traps, diffusers and other contraptions, he's come to the conclusion his room is too dead for music listening. He likes it for live recording though.

I agree with him, but the problem is not evenly distributed over the acoustic spectrum. This is where the real science and art comes in for treating a room. One would like it to have a consistent acoustic characteristic. A lively room may be enjoyable if the reflected sound is controlled. I think the problem with rooms that aren't obviously too live is that they are still "too live" at some frequencies and "too dead" at others.

As I said in the earlier thread, I've experienced an anechoic chamber, and in my opinion, it is not suitable for music reproduction. It is a very, very alien environment for listening. One does hear one's heartbeat, blood rushing through one's head etc. Even one's own breathing is a distraction. Sounds from other locations are muted. Even if one decided one liked this reproduced audio quality, the perceived efficiency of one's speakers would be substantially lower than in a conventional room. I don't know about bass reinforcement, the anechoic chamber at the McIntosh plant wasn't large enough for deep bass evaluation, but there was no reinforcement of mid-bass in the chamber I was in.

The closest one can get to experiencing this kind of "dead sound" (like an anechoic chamber) would be to take the audio reproduction system outdoors to an open area with no close surfaces to reflect the sound. At any distance beyond five feet or so, one gets sound level losses that degrade the quality of reproduced music. That's why outdoor sound reinforcement systems are designed the way they are, to focus the sound toward the listeners. This is often derided for audiophile reproduction, but then, a good outdoor speaker system will be overkill in a normal room.

[Rob Babcock]

True, you'd need a lot of power if the room wasn't reinforcing the sound.  I'm really curious how a nearfield 5.1 system would sound in an anechoic chamber.

[doug s.]

i tink, for audio listening, brian cheney's idea of live-end, dead-end is the way to go re:  sound treatment.  have the speaker end of the room dead, so ya get no unwanted reflections from the sound source - only hear the speaker.  have the end where ya sit be live, so ya get a good acoustic ambience...

ymmv,

doug s.

[JLM]

I vote for a "reasonable dampened" room.

As higher frequencies beam more than low.  Lower frequencies pressurize a room more than high.  So different frequencies behave differently.  I've also been in a couple of anechoic chambers and the sound is anything but "normal".  And I agree that its nearly impossible to treat a room to that extent, I believe Frank knows this and was exgagerating to emphasize his point.

Conventional advice recommends avoiding "early" reflections (0.1 - 10 ms, which translates to roughly everything within 10 feet of the speakers) so that the ear/brain does not have to sort out the "correct" direct signal from reflected that arrive at nearly the same time.

Simple absorption works for mid to high frequencies, but becomes impractical for bass notes.  That's where bass traps, diffraction devices, etc. come in.


IMO its improper to ask one vender to critize what another vendor has stated on his own forum.

[audiojerry]

IMO its improper to ask one vender to critize what another vendor has stated on his own forum.

I believe this needs to be stated within a larger context. If one vendor were being asked to criticize another vendor's product, perhaps this view would have more merit, but neither was done in this instance. I did not ask one vendor to criticize another vendor's product, not did I ask one vendor to criticize another.  

This is a discussion forum. Anyone posting their views here should expect the possibility that others may respond and comment. I merely posted the viewpoints of a fellow AC member (not as a vendor), and asked for the viewpoints of other members who might have extensive experience on this subject matter because I believed it might stimulate some healthy discussion on a topic of interest. Isn't that one of the reasons we all participate in this forum?

[Kevin P]

Mr. Linkwitz has some good reading on his site.

http://www.linkwitzlab.com/rooms.htm#Standing%20waves

Also if you want to do some calculations based on simple models.

http://cgi.guidetohometheater.com/cgi-bin/showoldnews.cgi?388

For my own dedicated listening room I'm choosing room dimensions that spread resonance as evenly as possible (even though the model is imperfect).  All the building materials are chosen to keep the model as accurate as possible.   I'll then measure with tone burst test signals to identify problem areas and I'll treat the room in response to those measurements across the listening area.  The idea would be to dampen any problem nodes via bass traps or other acoustical treatment and to shorten the “ringing” time of the stored energy in the room.  As SL points out this isn't an exact science by any means.  I'll also use Parametric EQ on the bass to deal with some of the peaks in room.

Second phase is using movable and adjustable treatment at first reflection points on the wall, ceiling and floor.   Some simple measurements will be used to try and relate the measurements to subjective preference but I'll choose how much & type based upon subjective preference.  

Third phase is to add some diffusion and reflection in the rear, ceiling and between the speakers.  All of this will be chosen based upon subjective preference.

I have three goals for the entire project.

#1.  Demo area for the gear I sell.

#2.  Evaluation/measurement lab for gear.

#3.  Personal enjoyment.


To answer the original post though.... I have no desire to build an acoustically "dead" room.   Assuming "dead" means that all sound reflections are attenuated so that the direct radiation wave is over emphasized in relation to reflected waves.

[nathanm]

Here's a thought:  Would listening to speakers in a true anechoic chamber be akin to listening with headphones or does it still sound like speakers?

Where did you get to visit one Jerry?

[8thnerve]

Here's a thought:  Would listening to speakers in a true anechoic chamber be akin to listening with headphones or does it still sound like speakers?

No, with headphones, you never hear sound from the right channel in your left ear and vice versa.  Even in an anechoic chamber, your will get crossfeed from the opposite channel.  Some headphones amps try to simulate this with crossfeed circuits.

Assuming that speakers would sound perfect in an anechoic chamber is also assuming that the recording was perfect, and since there are so many dissenting opinions on how to get the best stereo recording, we aren't quite there yet.  As it is, we DON'T listen in anechoic chambers.  So you can try to get close to one (which will never work in my opinion) or try and equalize the room as much as possible to get rid of the BAD parts of reflection and distortion.  We aim to do the latter.

Best Regards,

Nathan Loyer
Eighth Nerve

[MaxCast]

Do first and second relections affect the original wave or just your ears?

[WilliamL]

Max,

The first reflections affect the wave(s) which affect your ears. Remember that sound does not travel like light in a straight line, as reflection points are reached, the nature of sound waves are affected by a number of factors. I will let Nathan of Eighth Nerve elaborate on this a little more, but you can try some experiments at home by walking around your room and speaking towards the points of reflections and see how the nature (percption) of your voice changes.

Cheers,
Bill

[MaxCast]

Max,

The first reflections affect the wave(s) which affect your ears. Remember that sound does not travel like light in a straight line, as reflection points are reached, the nature of sound waves are affected by a number of factors. I will let Nathan of Eighth Nerve elaborate on this a little more, but you can try some experiments at home by walking around your room and speaking towards the points of reflections and see how the nature (percption) of your voice changes.

Cheers,
Bill

Interesting.  I understand first relections arriving after the original which is an issue.  I never thought about first relections creating havoc with the original wave.