helmholtz question

I was wondering if anyone has any info on how the thickness/density of the insulation placed against the slats will affect the frequency response. I've done multiple searches and I haven't been able o tfind much info. I ask because I've contemplated seperating my 4" rockwool into 2" peices for use in the helmholtz resonator if it doensn't make much difference. Thanks

mud, It shouldn't matter too much whether 4" or 2x2" is used. I don't know if it will help with this particular question, but Chris Whealy's Porous Absorber Calculator spreadsheet might help you with some of the calcs: http://www.whealy.com/acoustics/index.html All the best,

Hi, thanks for the info but that is not quite what I meant. I meant will it make a difference using 2" rockwool as opposed to 4" rockwool.

OK. For that question, the Whealy spreadsheet should help. :) All the best,