Post by Hexspa on May 23, 2016 14:01:35 GMT
There's been talk about pink fluffy (not dense) vs rigid boards and how well they work at different thicknesses with and without air gap.
From what I gather, exact gas flow resistivity numbers are hard to come by partly because of sample variation and testing methods.
Anyway here are some resources to help get us started. Presently I'm building superchunks out of Johns Manfield R19. According to the chart below, which may not be 100% accurate, it's resistivity is 1674 rayls or whatever. Rigid board will generally fall in line with the second, linear chart. You can then plug those numbers into the Acoustic Modelling calculator and see what kind of absorption coefficient you get.
www.acousticmodelling.com/porous.php
Have fun,
-m
From what I gather, exact gas flow resistivity numbers are hard to come by partly because of sample variation and testing methods.
Anyway here are some resources to help get us started. Presently I'm building superchunks out of Johns Manfield R19. According to the chart below, which may not be 100% accurate, it's resistivity is 1674 rayls or whatever. Rigid board will generally fall in line with the second, linear chart. You can then plug those numbers into the Acoustic Modelling calculator and see what kind of absorption coefficient you get.
www.acousticmodelling.com/porous.php
Have fun,
-m
