Good morning! Since I'm an allergic subject, I'd like to use a valid alternative to fibreglass as damping material. Any suggestion? Thanks in advance! Vincenzo
Wayne Parham Messages: 18756 Registered: January 2001
Illuminati (33rd Degree)
Some people use polyfill, like what's used as batting in pillows and winter coats. I find it to be awkward to use, because it doesn't hold together well. "Acousti-stuff" is a branded polyfill, packaged and sold by Parts Express. Ultratouch is a cotton product replacement for R13 that you might try.
Wayne Parham Messages: 18756 Registered: January 2001
Illuminati (33rd Degree)
Sure, wool will work. About your question on absorbtion at low frequencies, no fiberous padding of the thickness used for loudspeakers really works well at low frequencies. It doesn't need to though; It's really intended to attenuate midrange. If you needed a fiberous material that attenuated bass, it would need to be very thick. Another way to damp bass is to have a vibrating membrane with some resistance. That will move sympathetically and damp the waves by friction. But again, the damping material used in loudspeaker cabinets is there to attenuate midrange and higher frequency standing waves. The physical properties of the cabinet itself are what control the bass.
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