Been getting some conflicting info on this so thought I'd inquire here. For DIY bass traps, is there an advantage to using 2 x 703 panels (each panel is 2" thick totaling 6 lbs density) as opposed to one panel of 2" thick 705 panel (6 lbs density)? The only obvious difference here is mass so what if any, are the low-end performance differences.

Thanks.

quote:

Originally posted by drbam:
Been getting some conflicting info on this so thought I'd inquire here. For DIY bass traps, is there an advantage to using 2 x 703 panels (each panel is 2" thick totaling 6 lbs density) as opposed to one panel of 2" thick 705 panel (6 lbs density)? The only obvious difference here is mass so what if any, are the low-end performance differences.

Thanks.

Totaling 6lbs density? You mean the density of 2" 703 is 3pcf & you are totaling it to 6pcf? If so density is the same 3pcf, no matter how many 703s you use.

Here ya go
http://johnlsayers.com/Stuff/AbsorptionCoefficients.htm

Product 125hz 250hz 500hz 1000hz 2000hz 4000hz

703, plain 4" on wall 3.0 pcf 0.84 1.24 1.24 1.08 1.00 0.97
705, plain 2" on wall 6.0 pcf 0.16 0.71 1.02 1.01 0.99 0.99

703, FRK 4" on wall 3.0 pcf 0.88 0.90 0.84 0.71 0.49 0.23
705, FRK 2" on wall 6.0 pcf 0.60 0.50 0.63 0.82 0.45 0.34

Any questions?

Thanks!

Just a note on that.

4" of 705 will beat 4" of 703 below 125hz but I would recommend making them 6" of 703 which will out perform 4" of 705 and still cost less.

Glenn