[tkp]

I am very new to room treatment so I would greatly appreciate any help on the followings:

a)  Acoustic wedge foam.  Reading threads in this circle, I gathered that the minimum thickness is 3" for front wall treatment and first reflection point.  What are the benefits going from 3" to 4" to 8" thick foam?

b)  For low bass trap, I gathered that fiber glass pannel is the way to go.  However, I am very concern about fiber glass breakdown in the long run and potentially cause lung cancer.  Therefore, my choice is back to acoustic foam corner treatment.  Have any one tried the following corner treatment from foambymail?  If you have then I would greatly appreciate your input on which one is the most effective.

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

c)  Any recommendation other than acoustic foam and fiber glass pannels?

Thanks,
TKP

[Red Dragon Audio]

I am very new to room treatment so I would greatly appreciate any help on the followings:

a) Acoustic wedge foam. Reading threads in this circle, I gathered that the minimum thickness is 3" for front wall treatment and first reflection point. What are the benefits going from 3" to 4" to 8" thick foam?

if you are trying to treat upper midrange and highs, then 2"-3" thick should be plenty thick.  I'd say try covering a bit more surface area if your room is too "live" (lot's of glass, hardwood floor, bare walls, minimal furniture...that's a live room).
 

b) For low bass trap, I gathered that fiber glass pannel is the way to go. However, I am very concern about fiber glass breakdown in the long run and potentially cause lung cancer. Therefore, my choice is back to acoustic foam corner treatment. Have any one tried the following corner treatment from foambymail? If you have then I would greatly appreciate your input on which one is the most effective.

Fiberglass only is a problem if you cut it and breath in the particulates.  It doesn't break down on it's own.  To really prevent it from being  problem, just get the stuff that is faced with foil/paper (FSK/ASJ) and then cover it in fabric.  They will still function very well as bass traps and you won't have to worry one bit about stray fiberglass.

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

c) Any recommendation other than acoustic foam and fiber glass pannels?

Thanks,
TKP

I can't think of any off the top of my head.

[ooheadsoo]

There's no risk of cancer with fiberglass at all.  Don't know who started that myth.  It just makes you itch.  Don't beat it with a stick.  I'd go with fiberglass all the way around.  Why bother with foam?  

As for low bass, I would either go with a Jon Risch quick and dirty trap over just a slab of rigid fiberglass or attempt to build the trap that Ethan Winer describes on one of his two websites, but Ethan's would take some skill to do.

[tkp]

There's no risk of cancer with fiberglass at all.  Don't know who started that myth.  It just makes you itch.  Don't beat it with a stick.  I'd go with fiberglass all the way around.  Why bother with foam?  

As for low bass, I would either go with a Jon Risch quick and dirty trap over just a slab of rigid fiberglass or attempt to build the trap that Ethan Winer describes on one of his two websites, but Ethan's would take some skill to do.

I am not sure if this mean any thing but I am a bit worried.

http://consumerlawpage.com/article/fiber.shtml

[Rob Babcock]

It can cause serious respiratory problems, but it must get airborne to do that, and very small amounts probably aren't much of a threat.  I wouldn't want naken fibreglass around, but most recipes call for cotton/poly batting that contain the fibres.  It wouldn't alarm me any, but I've worked around 'glass and am always careful with it.

[warnerwh]

If you build your own bass traps ala Risch style like the ASC traps (easy) or his quick and dirty(easier) then you can cover the fiberglass with batting and burlap as thick as you like.  Realtraps also has a diy trap that is easy to do.  I doubt fiberglass could cause cancer but it will float in the air and cause other problems if you breath much of it.
 And yes it is best to use at least 3" foam.  This is the answer I've found from everybody who knows about room acoustics.  You are wise to learn about room acoustics as it is a major component of your sound and will affect it in a major way. Do a search over at AA in tweaks asylum and also the Rives audio asylum.  Some good reading at Ethan Winers realtraps site as well as Rives Audio.
 When I first was learning I bought a bunch of 2" and it helped significantly. Then read where I should  use at least 3" and put the 3" in.  It was well worth the little extra money.  My new listening room is LEDE and is done in 3" and 4" wedge foam along with several bass traps.  The bass traps actually also help make the midrange sound clearer due to controlling the bass.  Also the benefit of having good room acoustics has a very good bang for buck value.  Those corner foam bass traps aren't very effective although will do some good. For the money you're much better off building bass traps that are very effective.

[ooheadsoo]

Well, you don't want to stick your head in a baft of fiberglass and breath deeply.  You wouldn't want to grind up a roll of carpet and breath in deeply either.  Perhaps this would give some better perspective: http://www.guardianfiberglass.com/printouts/eng_msds2.htm

[John Casler]

I am very new to room treatment so I would greatly appreciate any help on the followings:

a)  Acoustic wedge foam.  Reading threads in this circle, I gathered that the minimum thickness is 3" for front wall treatment and first reflection point.  What are the benefits going from 3" to 4" to 8" thick foam?

b)  For low bass trap, I gathered that fiber glass pannel is the way to go.  However, I am very concern about fiber glass breakdown in the long run and potentially cause lung cancer.  Therefore, my ch ...

Hi TKP,

If I remember correctly, the two most glaring areas of your room that needed treatment help were the RPTV between the speakers, and the large wooden table in front of the sofa.

The wooden table will cause the "worst type" of early reflection smear, because it causes a reflection that is very close in timing and amplitude to the main direct signal.  You will be totally surprised at what you formerly thought was detail and imaging.

I would suggest a nice soft cloth table cloth (or similar) that could be left on for movies.

Then for "serious" 2 channel listening, you need to cover most of the table with 4" wedge sheets (leave the table cloth) with the wedges oriented from left to right (not front to back)

Same for the  RPTV.  Get a 48" x 48" x 4" (or size that fits the TV better) and find a way to drape, or attach it to the front of the RPTV when seriously listening.

These should be oriented with the wedges running "vertically" for best results.

I was under the impression that your bass was quite good so it probably doesn't need any treatment???

I think you'll find that the two treaments above will show you a system sound you had no idea existed

As far as foam thickness, I am a beleiver in 3-4" minimum in most applications.  If you want to see how "little" sound is blocked or absorbed by your foam sheets just place a single sheet in front of the speaker.

A 3 inch wedge could almost be used as a "grill".  Luckily when used in most applications, the sound has to pass through it "TWO TIMES" to get back to you, so it is a little more effective than the experiment.

Your next areas to work on would be:

Areas of First Reflection
"ALL" two boundary junctions
"ALL" three boundary junctions

Bass treatments will really depend on your room and its dimensions.

But to recap, I think you'll hear a very nice improvement by simply Acoustic Foaming the RPTV and that coffee table. (throw them in the closet when your done)

Have fun.

[tkp]

Greatly appreciate for every one input so far.

John,

I already figure out the treatment for the main room.  I plan to build two pannels of 2' x 5' and 3' x 5' of 4" wedge foam to treat the upper section of the TV cabinet and the lower section of the TV cabinet.  I have no problem with low bass because the room is wide open with no corners near by.  I normally move the coffee table out of the way when watching DVD or listenning to music.

My questions has to do with the second room upstair.  

http://www.audiocircle.com/index.php?action=gallery;area=browse;album=233

As you can see, the room is small (12 ft L x 11 ft W x 8ft H).  The left speaker will be close to a corner which will need bass trap.

Base on the input so far, I am going to get 3" wedge foam for the front, the left side wall, and cover the TV.  As for the corner, I have to decide between fiber glass pannel or some thing else.