Sound Damping and absorption material

Hi Craig,

Sorry for any ambiguity in my post; I was making a general comment, not replying to your suggestion, which works well. I would add that if the damping material is solvent-based it should be given adequate time to release said solvents before the drivers are installed.

Cheers, Carl.

No worries, Carl! And you are absolutely correct about allowing any solvent-based material to flash off before driver installation. It’s always good to check the can for any curing time suggestions. I usually allow a couple of days in the shop with proper air circulation just to be sure for the roof cement.
 
Any absorptive material works most effectively in the open enclosure volume, not fixed to the walls where the particle velocity tends towards zero. Put another way, lining the enclosure walls is the most wasteful and least effective use of absorption.

That would only be true for frequencies below the Schroeder frequency of the enclosure where standing waves form. Higher frequencies would be effectively absorbed with a "wall" mounted absorber.

Your point is worth noting considering standing waves can be very problematic, even more so than damping the backwave.
 
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Roof cement. It can be troweled on to the cabinet wall and leaving it uneven mitigates the sonic problems associated with parallel walls. You can add lightness by mixing in bean bag styrofoam balls (I’ve used the small ones, about 1/8” diameter).
Thankyou Criag
I was thinking of using some sort of rubber/bitumen sheet and over that roof cement(i believe its same as black rubber paint?) to seal the cabinet. Will definitely give time to dry for a week, be it any form of paint just to be safe.

Purchased ROCKWOOK for sound absorption. Which i'll lay on top.

This is for Zaph SB12.3 sealed enclosure. Also do we have to cover all 4 sides of enclosure?

Any absorptive material works most effectively in the open enclosure volume, not fixed to the walls where the particle velocity tends towards zero. Put another way, lining the enclosure walls is the most wasteful and least effective use of absorption.
Thankyou, I am not sure if i understood correctly. Are you saying that just absorptive material is sufficient?
I want to handle vibration as i'll be using wood. Its a sealed enclosure.
 
The acoustic damping is superb. I have not found anything better. It beats felt, fiberglass, rock wool
I’m a little unclear on whether melamine foam works for absorption, panel damping, or both. Most of the commercial sound products promote it’s sound absorption characteristics, but does it also work well to line and deaden cabinet walls?
 
Mostly absorption and it makes the cabinet ever so slightly larger in appearance to the woofer. For damping get air conditioning damping sheets from the hardware store, they are just like the expensive brand name damping sheets at a fraction of the price. They are foil backed sticky rubberized sheeting like used in cars to stop the rattling of the body.