Acoustic Treatment Research Material

[HDJK]

Originally Posted by RUR

Either this gent lives alone or his significant other is extreeeeeemely tolerant.


http://www.stereopal.com/HomeVisit/William.htm

Egg crates and a violin "strategically placed in the center of the room. It reflects sounds and reinforces the image of vocals and other instruments"

Thanks to sleepysurf @ MLC

Believe it or not, i have heard the sound of the room BEFORE and AFTER the placement of the egg cartons.

They do work ! The room use to be full of bass resonance problem, but they are not truly a thing of the past due the "diffusion" effect of the egg cartons.

Due to the structure of the bolded sentence I can actually believe that quote

Egg crates do NOT diffuse anything considered as 'low frequencies'. They will certaily suck the high frequncies out of your room and leave it sounding dead. If one likes that kind of thing...

[RUR]

Originally Posted by plowmanjoe

....so i have a few questions, will painting these take away from their function. and is the owens corning 703 material more ideal than the oc r-13 (pink fluffy stuff)?

3.5" of OC R-13 compares very favorably with 3" of OC 703 as shown on the Bob Golds site: http://www.bobgolds.com/AbsorptionCoefficients.htm

Ideally, you would cover the insulation with an acoustically transparent cloth (don't know how canvas fares) and, no, it's generally not a good idea to paint them, since the paint, itself, is often quite reflective. Dying the material is a much better way to go.

Edit: Here's a couple of by-the-yard sources for Guilford of Maine's acoustically transparent fabric, available in a wide variety of colors. This is the stuff commonly used by makers of treatment panels, etc.

http://www.acousticalsolutions.com/p...FRg6awodwnwgfQ
http://www.fabricmate.com/guilford.p...FQsQagod82Blfg

[mattym]

We have been doing fabric printing for around 3 years now, Auralex's brochure makes it sound like they invented it..and the performance isnt all that either.

more links for the thread

www.rpgeurope.com - uk and european manufacture/distribution for RPG
www.homecinemachoice.com - http://www.homecinemachoice.com/sound_sense for a dedicated acoustics column

1" High Density fiberglass is ok for use in some areas,
2" High Density fiberglass is good for use in most areas
4" High Density fiberglass is excellent for use in most areas

Diffusion and Bass Tools should be employed in combination with absorption, absorption on its own is not enough.

4" of material with have SIMILAR acoustic properties as 2" with a 2" airgap, its all down to particle velocity, in general an airgap will increase the performance of the material being used

Cheap foam is a waste of time, if it hasnt already gone yellow it will do. Also, cheap foam isnt as effective as the expensive brands.

Foam bass traps..well...they dont

A 4" piece of fiberglass IS NOT a bass trap, its more a broadband absorber.

i will think of more useful info...

[mattym]

Originally Posted by RUR

3.5" of OC R-13 compares very favorably with 3" of OC 703 as shown on the Bob Golds site: http://www.bobgolds.com/AbsorptionCoefficients.htm

Ideally, you would cover the insulation with an acoustically transparent cloth (don't know how canvas fares) and, no, it's generally not a good idea to paint them, since the paint, itself, is often quite reflective. Dying the material is a much better way to go.

Edit: Here's a couple of by-the-yard sources for Guilford of Maine's acoustically transparent fabric, available in a wide variety of colors. This is the stuff commonly used by makers of treatment panels, etc.

http://www.acousticalsolutions.com/p...FRg6awodwnwgfQ
http://www.fabricmate.com/guilford.p...FQsQagod82Blfg

canvas will produce some LF absorption, but little else.

[Big Daddy]

These cool Acoustic Art room treatments from Synergistic Research are the most unusual looking treatment material I have ever seen. Make sure you click on each one to get additional information. You can buy them at The Cable Company.

[mattym]

Originally Posted by Big Daddy

These cool Acoustic Art room treatments from Synergistic Research are the most unusual looking treatment material I have ever seen. Make sure you click on each one to get additional information. You can buy them at The Cable Company.

i especially like all the before and after measurements to back up the claims, and the extensive testing results...

[FILM BUFF]

Originally Posted by mattym

i especially like all the before and after measurements to back up the claims, and the extensive testing results...

I especially like the fact I can take these devices home, set them up in under an hour, and then listen. If I hear nothing I can send them back from whence they came. I've been following this product since finding out about it after the Rocky Mountain show. I am amazed at the rancor some show while trying to disprove it while discounting anyone who professes to have heard and liked the effect.

I've got a set on order and I'll make up my own mind. And please don't tell me I can't trust my own ears- whose ears am I to trust? Yours?

[mattym]

if you get them and hear a difference, a real, tangible difference, then I will be impressed, however as an Acoustician, with over 15 years service, and many brushes with products that claim to do things that they clearly dont, I am sceptical. As for taking them home and setting up in an hour, buy freestanding panels and have them set up in just as little time.

The question is, if they work so well, why not get the room measured before and after? That is concrete, black and white proof that they work and are not just subjective.

[FILM BUFF]

mattym,
I've got a room that is currently treated in the LEDE tradition. The Acoustic ART System is arriving sometime this morning (I hope- Christmas shipments may hold delivery off until Monday). In any rate if I hear a difference, a significant and tangible improvement over my already excellent listening room, the I too will be impressed.

[mattym]

did they arrive?

do you have any diffusion in your room or is the traditional absorption only for DE bit of LEDE?

i would imagagine the monks gaff that the guy went too sounded good due to the large amount of diffusion that the walls and room would have had with lots of little bits and pieces all over the place, much like the old concert halls...

Please, i would be very interested to get your impressions of the devices, i AM cynical, but at the same time, I try and keep an open mind...

[saprano]

What do you guys think about this companie?

http://www.atsacoustics.com/

[mattym]

absorption figures look ok, but the material is likely soft and squidgy, thats not a bad thing but longevity might take a hit if they are made of the softer material.

Edit

just read the page a bit more carefully for the 2" panels

Absorption Coefficients
1/3 Octave Band Center Frequencies, Hz
125 250 500 1000 2000 4000 NRC
0.27 0.55 1.07 1.10 1.10 1.10 0.95
Data based on test results from the mineral wool absorption material used in our panels, and independent testing of our 4-inch panels by RAL, a leading acoustical laboratory.

data based on? surely that should be ASTM measurements of the actual products in a test chamber? to be honest, if they cant publish the correct figures for the correct panels, then avoid. Make your own instead.

[blu master]

So let me get this for ex in my room the bass way better in one corner so in order to get that sweet bass in the sweet spot where i sit i just need some acoustic panels?

[mattym]

Originally Posted by blu master

So let me get this for ex in my room the bass way better in one corner so in order to get that sweet bass in the sweet spot where i sit i just need some acoustic panels?

well if you have your speakers and subs all set up correctly and positioned right and its still sounds wrong then yes, some of the correct type, in the right place will help...depends on the room size, speakers etc.

Dont go and buy some foam that claims to cure your bass problems because it really wont.

[saprano]

Originally Posted by blu master

So let me get this for ex in my room the bass way better in one corner so in order to get that sweet bass in the sweet spot where i sit i just need some acoustic panels?

Yea all my bass goes to one corner also, i hate that

Bass still sounds go at my listening spot, but when i move to corner on the other side of the room.......

Maby i should put the sub there?

[mattym]

air pressure is highest at the corners of the room, thats why most bass traps are corner mounted to make the most of it. Bass traps in the corners are good.

Put the sub at your listening position, then go around your room and stand where you would like to put the sub(well, get down to listening height) and when the bass sounds good, put the sub there and try your listening position..its not a good way of dealing with the room, but it makes the bass good at your listening position

[FreddieFerric]

I just installed six acoustic panels in my audio room and am really impressed with the noticable improvement that they make to the overall room acoustics. Echoes, reverbs, standing waveforms are all gone now. As a test I put on Eric Clapton's Pilgrim CD (which I thought was an audio nightmare for pre-panel setup) and am amazed at how truly detailed and lush the music is now.

The way that my HT is set up makes it practically impossible for me to really use acoustic panels for that application. The other part though is that my wife wouldn't stand for it from a purely artistic point of view. (It also doubles as our living room). Still, now I'm really starting to wonder about how much improvement I might hear if I could use them in my HT application.

Anybody using them? I'd like to know your before and after experiences.

[mattym]

for cinema rooms you should get a good result there too, depending how the room is laid out..i always try and balance a room as much as possible, that helps with imaging and balance of the sound.

[naturephoto1]

Here is a good source for acoustic foam:

http://www.foambymail.com/Products.html

Rich

[mattym]

real traps did a comparison between FBM and their own products, they concluded that FBM sucks. I have no experience of it myself, so cant comment further at this point