Cylinder bass trap??

[joeparaski]

A local guy has 4 acoustic panels for sale measuring 4' by 2' and 2 "cylinder" bass traps. I've never heard of cylinder style acoustic panels, they look like really tall SVS subs with a foam wrapping around them.

He wants $250 for all 6 pieces. Does anybody have any info regarding the effectiveness of these cylinders?

Joe

[Gaara]

Cylinder bass traps are usually Helmholtz resonators, which are a very specific type bass trap. The size of the opening is tuned to trap a specific frequency, so they only work over a narrow band. The thought was that instead of using a bunch of broad absorption panels you could get away with fewer Helmholtz resonators tuned specifically to the rooms modes.

Chances are they are setup specifically for his room, and will not work as well in yours unless you have similar rooms. 8ft ceiling are common and if he built on to take care of that mode it will be useful. The others may not be.

They could also be tube traps which are not as common. These are like regular bass traps just much larger to be more effective at lower frequencies. These are very different traps as they are open top to bottom, generally they are made with lots of absorption material in the middle with acoustically transparent cloth on the outside.

Ask him if they are tube traps or Helmholtz resonators, and if they are the latter find out what frequency band they are tuned to.

Jared