Can canvass be used for Bass Traps?

Craig B · Post by **Craig B** » Sun Dec 04, 2005 10:12 pm

I was just wondering if Canvass can be used for Bass Traps?

I just built one with Canvass on one side and Burlap on the other.

I just found the burlap quite unattractive so I covered the room side with off white Canvass.

It is 2 feet wide and 7 feet high & 4 inches deep with 2 inches of 702 type fiberglass.

Will the Canvass reflect sound back into the room instead of absorbing?

If so, I guess I can use it as a Gobo possibly.

I am anxious to hear some input.

knightfly · Post by **knightfly** » Mon Dec 05, 2005 8:16 am

As a bass trap, a canvas cover should work fine; I'd think it would act similar to the FRK facing on some rigid insulations, which actually improves bass absorption on a corner trap; it will also reduce higher frequency absorption, which isn't always a bad thing... Steve

Craig B · Post by **Craig B** » Mon Dec 05, 2005 8:31 am

Thanks for the reply.

I have included some photo's of the construction.

I used 1 x 4 by 7 feet. With 2 inches of a similar product like 703.

I have burlap on the back and Canvas on the front.

The right corner with the brick is quite a challenge. My Monitors are 4 feet from the front wall and it is 12 feet to the rear wall. The room is 13 feet wide and 7.5 feet high to the drop ceiling.

knightfly · Post by **knightfly** » Mon Dec 05, 2005 8:40 am

You may also want to build a couple of gobo's like these

http://www.johnlsayers.com/phpBB2/download.php?id=2884

or on wheels, to be placed close to the rear of your speakers during mixdowns; otherwise, you may have fairly deep peaks/nulls in low mids due to SBIR. For that, probably 4" thick material would work best - and canvas should be fine there too; it's not going to see much high frequency, since tweeters are more directional and only the lows will diffract around the rear of the speakers and cause cancellations... Steve

Craig B · Post by **Craig B** » Mon Dec 05, 2005 8:52 am

Thanks again.

What is SBIR and how close should the Gobo's be to the rear of the monitor's.?

Or whould it be better to move my monitors closer to the wall.?

What is a good distance from the front wall?

4 inches of 703 type material for the Gobo's?

knightfly · Post by **knightfly** » Wed Dec 21, 2005 8:54 am

Topmost result of a search for SBIR -

http://www.johnlsayers.com/phpBB2/viewt ... light=sbir

HTH... Steve