Super Soundproofing Community Forum

Soundproofing Forum Topics => Acoustical Questions? Ask here about Sound absorbsion, Reflection, ETC => Topic started by: PeterPham on October 25, 2014, 09:33:34 AM

Title: Question about sound absorbing effect of EPS
Post by: PeterPham on October 25, 2014, 09:33:34 AM
Hi, I'm just wondering if EPS (expanded polystyrene) is good for sound absorbing, if I put it in the cavity of drywall stud wall. Thanks
Title: Re: Question about sound absorbing effect of EPS
Post by: Randy S on October 25, 2014, 02:55:09 PM
from the information I have reviewed so far, I would say your better off using a cotton fiber insulation, thermal fiber or roxul safe and sound.
I am not finding the NRC or STC ratings with detail assembly based on lab testing for this type of material.
Title: Re: Question about sound absorbing effect of EPS
Post by: art noxon on December 07, 2014, 01:27:44 AM
Take a long tube, maybe 4' long.  find some way to transmit sound through it so you can hear the sound at one end of the duct.  Use an FM radio tuned off station so you just get hiss.  Listen to sound thru the tube.  Pack the tube with various materials and figure out what works.  Use radio shack sound meter to actually measure the effects.  Let us know what happened.  My guess is that Styrofoam beads don't absorb sound, they are too light, too springy and make too much noise when touched. 

Art Noxon, Acoustic Engineer
President of ASC - TubeTrap/WallDamp