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Old 05-02-2007, 09:03 AM   #13
scottdru
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The foam panels you linked to are NOT bass traps. These will only absorb high and mid frequencies (and probably less effectively than the carpet you are using on the walls with this particular foam).

If you are going to use foam, you would need thick foam wedges to put in corners that are designed as bass traps, like these:

http://cgi.ebay.co.uk/2-off-3ft-Acou...QQcmdZViewItem

HOWEVER, while I am happy to see that this company (unlike a number of other companies selling cheap "studio foam" off ebay) provides certified lab reports, I can tell you from looking at their lab reports that the absorption specs on this foam is NOT very good, and you will be better building some DIY panels based on either Owens Corning 703 panels or the rockwool equivalent (i.e., same density) similar to Bubba's panels. I can assure you that these will be MUCH more effective, and will also have a much greater price/performance ratio.

There are a good many discussions on various forums about DIY 703/rockwool broadband/bass traps, with loads of interesting ideas and plans for building various types of frames for hanging these panels.

One good place to look (and ask) is Ethan Winer's acoustics forum here:

http://forums.musicplayer.com/ubbthr...tlist/Board/24

There's also the Sound on Sound "Studio Design & Acoustics" forum:

http://www.soundonsound.com/forum/po...=&Board=DESIGN

John Sayers' forum is good too:

http://www.johnlsayers.com/phpBB2/index.php

Quote:
Originally Posted by anytime732 View Post
i must say that is a very impressive idea but..... my studio is not that big and if i where to kit it out with that size of traps here would be no room for me!!!!!
Well . . . do you want accuracy or not? Low frequency room modes require mass, and a good amount of coverage, to address. Sorry . . . you can't defy the laws of physics!

It is very important to treat as much of your corner space as possible. You should start with the four vertical (wall/wall) corners, and then do the wall/ceiling corners

Any panels you mount flat on the wall should have a gap between the wall and back of the panel (I usually recommend about 3 to 4 inches).

This accomplishes a few things:

(1) it increases the low frequency absorption performance of those panels (i.e., the air gap causes it to act like a thicker panel), and

(2) it increases the amount of absorption surface that is usably exposed to the room.


Quote:
would it still have a significant effect if i where to 20"(width) traps on the between the ceiling and the walls as shown ( http://warsaw.innova-partners.com/~c...o/IMG_0284.jpg ) and then some pannels mounted flat on all four walls.........

i know that sounds a bit confising but would it have a good enough effect to justify doing it,,,,,,??
Yes, it would (though it will decrease the performance) . . . but it also adds to the difficulty in constructing the trap -- cutting fiberglass and/or rockwool is messy, itchy stuff.

I want to add another link that may be informative for you. To help you understand why it is so critically important to treat the corners of your room, read up on room modes and standing waves here:

http://www.isvr.soton.ac.uk/SPCG/Tut...ding-rooms.htm

This page has some excellent animations that show how low frequencies travel in a room, and demonstrates how all of the room modes gather in the corners. If you can interrupt the wave fronts at those corners, you will be able to reduce the amplitude of the reflected sound waves. Reducing the amplitude of these waves by even 6 dB in relation to the direct sound from your monitors will noticeably reduce the amount of acoustic distortion caused by the reflected sound interfering with the direct sound from your monitors.

Unfortunately for you, the smaller your room, the more you need bass traps!

Last edited by scottdru; 05-02-2007 at 09:07 AM.
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