Acousta-Stuf in a bass reflex cab?

[Fr3ak]

aside from the obvious problem of having the Acousta-Stuf coming out of the ports is it beneficial to put dampening products in a large bass reflex cab?

 

[TLS Guy]

aside from the obvious problem of having the Acousta-Stuf coming out of the ports is it beneficial to put dampening products in a large bass reflex cab?

You must not over damp a reflex or you will kill the box resonance Fb. A ported speaker is in essence the interaction of the speaker and box resonance. If you fill a ported enclosure full of dampening material, then you have a highly misaligned aperiodic transmission line.

 

[j_garcia]

Almost every vented sub I've ever seen uses some amount of fill, but there is definitely a point at which it is too much. The fill makes the driver behave like it is in a larger enclosure, so you want to keep it to a minimum because it will affect the tuning.

 

[TLS Guy]

Almost every vented sub I've ever seen uses some amount of fill, but there is definitely a point at which it is too much. The fill makes the driver behave like it is in a larger enclosure, so you want to keep it to a minimum because it will affect the tuning.

The usual rule of thumb is to cover 50% if the internal surface. Mineral wool products are best strategically placed to reduce reflections from the rear of the driver. You never fill the cavity, like an sealed or TL.

 

[j_garcia]

The usual rule of thumb is to cover 50% if the internal surface. Mineral wool products are best strategically placed to reduce reflections from the rear of the driver. You never fill the cavity, like an sealed or TL.

The sub I built I actually used 1" sheets of poly and stapled them to the walls of the enclosure. That was sufficient to tame the back wave.

 

[WmAx]

The sub I built I actually used 1" sheets of poly and stapled them to the walls of the enclosure. That was sufficient to tame the back wave.

That would not even be able to absorb lower midband energy, much less bass frequencies.

-Chris