Guess the frequency

[MDS]

The black sheets on the walls and up into the aluminum enclosure are vinyl sound dampening sheets - similar in concept to DynaMat although I don't know if they are better or worse than DynaMat.

The dampening sheets helped a bit but the real issue I think is the cavernous enclosure and the high velocity of air being sucked in due to a very high fan speed. The acoustic foam did more to reduce the noise than the sound dampening sheets.

 

[avaserfi]

Have you thought about possibly using these filled with mineral wool? It seems they could fill the area without damaging air flow if properly placed and that would be able to contain the wool while allowing for pretty good sound absorption.

 

[MDS]

I looked at the ReadyAcoustics link the last time you mentioned it. That could work but they are 2' x 4' and would have to be cut down.

 

[avaserfi]

You could just fill the bottom half and fold the rest over, that would work. With proper placement it looks like 2-3 would be more then enough.

 

[Joel DuBay]

I looked at the ReadyAcoustics link the last time you mentioned it. That could work but they are 2' x 4' and would have to be cut down.

Stay tuned for additional size options coming soon.



AND!!!! Don't forget to sign up for the FREE room treatment package AudioHolics and Ready Acoustics are giving away.


Thanks all!


Joel DuBay
Ready Acoustics.com
Bass Traps and DIY Acoustic Panels

 

[j_garcia]

They also make spray on version of damping material like Dynamat as well, just something else to consider.

 

[bpape]

I suspect that a lot of the noise is not the duct itself but more the vibration of the structure itself. To isolate that, one would need to consider redoing the ducting to not attach directly to the structure and also potentially make it from a material other than tin.

Bryan

 

[Alex2507]

Today I checked at work and the black 1" thick insulating material is refered to as duct liner. It is either mold or mildew resistant. Ducts all over Boston are lined with this stuff to reduce the noise of moving air. In your case I would try to line the blower motor enclosure. Another place I have lined with that stuff is the difuser in the TV room. Good luck.

Alex