Question for Jarred

[Guest guest]

Jarred, what is it about foam that makes it so useful for soundproofing?

[Guest guest]

" Jarred, what is it about foam that makes it so useful for soundproofing? "

Foams are often used in recording studios to reduce echo; open-celled foams do

this by allowing the moving particles into its matrix, and reducing their speed

by way of increased airpressure and friction. The reduction value of the foam

is largely based on how much surface area is exposed to the air. This is one

reason why eggcrate foam is useful, apart from the fact that the points jutting

out help with low-frequency, as longer wavelengths need more foam to move though

to slow them down. when adheared to a surface, the foam helps to remove surface

vibrations. It's like when you hit a table with your hand (or a wall with your

head), the table continues to vibrate, producing more sound. The foam not only

slows the sound down, but also helps with this impact reverberation(again, if

its adheard to the surface, not hanging apart from it). I've heard that

closed-cell foams on the other hand, are better for low frequency, though this

would not be the case with closed-cell foam insulation, as it is far too rigid.

A closed-cell foam for soundproofing must be soft, so that it can give when it

is impacted by comprssion waves. Closed-cell foams are also good to use as

anti-vibration pads for washing machines, machinery, beds, etc. Final note, one

of the main differenced between regular and acoustic foams , is that acoustic

foams are generally heavier so that they require more kinetic energy to move,

and thus disapate more energy.