Sand trap

[kadoi]

Being fairly new to the DIY world I run the risk of sounding ignorant here, but has anyone built a subwoofer enclosure the incorporated a sand filled enclosure around the box itself? Seems to me that it would be more effective than bracing or concrete. Then just add the internal filling to negate standing wave resonance.

 

[revboden]

it won't do anything to negate standing waves in the box but it will damp panel resonances through materials impedance mismatch. I have use silicone sandwiched between the inner and outer panels to do this, it's lighter than sand and does the same thing.