ok.. i've spent like 3 days reading Cojos building thread (good job, man..) and i'm a bit curious to the differences btw a 4" bass trap and 6".. What i've gathered so far is the 6" is better, but I want to know how much better, real world application-wise.

And how far should they be from the wall after you built them...?

Do you leave an air space when making bass traps?

Is there a difference from having it got from floor to ceiling or is it better to leave it as 4 feet?

so upon FURTHER reading, i'm finding out the difference btw 4" and 6" using OC 703 is (according to bob golds data), negligible... Its actually better...

703, plain 4" (102mm) on wall 3.0 pcf (48 kg/m3) 0.84 1.24 1.24 1.08 1.00 0.97 1.15
705, plain 4" (102mm) on wall 6.0 pcf (96 kg/m3) 0.75 1.19 1.17 1.05 0.97 0.98 1.10

But what about the space from the wall.. Is 2" ok for a 4" thick trap?

Umlaut, those specs are both for 4" panels, with one made from 703 and one made from 705.

6" panels will have better performance at lower frequencies, all else being equal. However, bass trapping is also about coverage area, so if you have a certain amount of material you're better off covering more corners with 4" panels. If you still have material left after all the corners are covered and you have your RFZ, then you can start making the bass traps thicker.

As far as spacing, a good rule of thumb is to have the space be the same as the panel thickness, ie, 4" panel 4" from wall, 6" panel 6" from wall.

Just to clarify, it gives you more sabins (better performance) on all frequencies if they are made with the sides open. Part of the reason our Monster trap (6") out proformas our GIK 244 (4") so well. Every thing else you said though I totally agree with. thumbsupthumbsup

Glenn

If you're going to have them mounted flat parallel with a surface like on the rear wall of the room, then you can gap them up to 6" (assuming 6" thick panels). It's diminishing returns to have more gap than absorbtion (2" go to 2" gap, 4", go up to 4", etc.)

Corner mounting builds in the gap so to speak when you straddle it. You get a variable depth cavity.

Bryan

Are the sides still open if the Monster trap has the optional wood frame like your photo shows? The photo is a little small so I can't see if there's holes in the side of the wood.

That picture is the GIK 242 elite (wood frame) with a wood stand. The Monster would have the wood stand but the sides would be open.

Glenn

whats the best way to space a homemade bass trap intended to hang from a wall? i can think of a couple ways, like cutting the wood with a couple "legs" on the back of it or hanging it from the ceiling an appropriate distance from the wall, but i'd like to hear if anyone has any better, simpler suggestions.

If you are hanging it like a picture you could cut a piece of PVC pipe to 4" and slip that between the panel and the wall. I like your idea of making little legs for the back though. Maybe a stopper for a door would work the same.

Glenn

thats a great, great idea. not sure how the pvc would work; maybe i'd just need to see it.

time to go wander around the hardware store and see what develops. what about the walls themselves? i worry about supporting that much weight.

Welcome To OOK's!!! the pro picture hangers. Can be found at any major hardware chain.

Glenn

i actually came up with a solution that im really psyched about. as soon as i can get someone with a camera over, i'll post up some pictures of my space.