Honeycomb composite panel enclosure, dual opposed configuration

[rhapsodee]

Has anyone tried building a subwoofer from honeycomb panels? They would be very light, yet have high stiffness. Not sure about the damping characteristics of the panels vs plywood though.

Basically beam bending theory, kind of like an I beam, the material far away from the middle is doing all the work, so the honeycomb core with the composite panels.

The resultant enclosure would be very light, so will likely have to use dual opposed configuration to cancel out vibrations .

Any thought and comments?

honeycomb composite panels - Google Search

[454Casull]

No point in building the enclosure out of it, as you can make a regular enclosure stiffer by specifying thicker walls

As for the sub diaphragm, B&W did that with their Rohacell

[planet10]

But a thicker wall would increase the mass.

I think this would be an interesting project. With push-push woofers, little energy gets into the box, i'd look at the opposing baffles, and push-push drivers as a subassembly, with the light weight composite panels as a "cover" for the 4 open sides. Feet could be loaded into the baffle bits.

dave

[Djim]

Honeycomb panels can work if you glue lots of panel bracing in (intersections of about 4 to 5 inches) and you could use a few plastic tubes (fill them with fibre) for wall to wall bracing (use strong 2 component glue for that) . After you’re finished you could ‘paint’ the inside with a thick layer of liquid rubber. Or do it the old fashion way by melting a layer of roof felt (or clean pitch) in each intersection. If you want to keep weight to minimum spray glue on the inside with ‘felt flakes’ (correct English word?) on top. That’s the same technique the use for panels in cars but is a little less efficient in damping. Of course all these measures will increase mass but it is still light.

[454Casull]

Originally Posted by planet10

But a thicker wall would increase the mass.

So? Increasing the thickness of the wall increases the mass proportionally (and mass is not always a bad thing), but increases the stiffness by the cube.

[Rademakers]

I've build an composite enclosure but am still in the testing stage. In due time I will release more info about it.

Best regards Johan

[sq225917]

if you want to make the subwoofer lighter, maybe a little bit smaller, then try it, but it probably won't sound any different.