Damping/Stuffing Comp. Chamber on BLH (Off Topic)
by BobW 
, Tuesday, June 13, 2006, 13:19 (6527 days ago)
What is the general feeling about damping or stuffing the chamber behind the driver in Back Loaded designs? The driver is the Fostex FE206 ESR & cab. is their recommended design.
[img]images/uploaded/image120.jpg[/img]
Damping/Stuffing Comp. Chamber on BLH
by Bert , Tuesday, June 13, 2006, 23:10 (6526 days ago) @ BobW
Hi Bob,
What is the general feeling about damping or stuffing the chamber behind the driver in Back Loaded designs?
A good design does not need damping material. Damping is needed in some combinations but usually you do not only damp away problems but also some of the nice things a horn provides.
Most important is to reduce the reflections from the wall behind the driver. Usually this should be done with angled panels but diffraction helps too.
Either way, when the back wall is close to the driver then the energy needs to be dampened. Felt usually works rather well but too much applied to the back wall also takes away life...
The only advice I can give is to play with the damping. Start empty, add some pieces of felt (10-20mm thick) to the back wall and listen. If it turns out that you need to reduce too much hollowness after then you could add some damping material in the space below the driver (never directly behind it!) and listen again.
Ciao,
Bert
--
BD-Design - Only the Best!
Damping/Stuffing Comp. Chamber on BLH
I agree fully with what Bert has said. For some time I ran with no more than very thin felt stuck to the rear wall of the compression chamber - no further stuffing.
More recently I upgraded the thin felt to 10mm wool felt. This allows the drivers to be run at higher volumes without any reflections (distortions) intruding on the sound.