DIY monitors from composite material??

[heffree]

i posted this over at the groupdiy forums but i figured i'd posted it here as well to get some more input.


i've had a bit of interest in learning about composites lately so i've enrolled in a class at the local tech college where i live.
seeing as how i have access to completely free materials (carbon, fiberglass, kevlar) i figured i may want to experiment with using these materials in a few audio related projects.

i have noticed some companies using fiberglass or graphite carbon composite for things like acoustic guitars and acoustic drums, but not a whole lot about speaker enclosures.
does anybody here have any experience with such an enclosure from fiberglass or carbon composite? would it even be worth it (time-wise; cost is not an issue) to try making one?

[gooki]

The car audio folk quite often make FG enclosures to fit tight spots. Wood frame, stretched with fabric to for shape, then resin and glass to add strength.

Ive done it once for a pair of mid woofers to fit my dash. Works well so all i can say is do it.

[gedlee]

I have made composite enclosures in fiberglass and Carbon fiber. I stopped using these materials along time ago. They are outrageous to work with (expense and time) and the advantages are minimal - almost nonexistant.

And please remember that a speaker is NOT a musical instrument. It does not want to have a "sound" like a guitar, or violin. It wants to be "soundless". So any comparison of materials between a musical instrument and a loudspeaker are probably incorrect.

About 30 years ago I taped together some boxes out of cardboard that just fit into a small and complex space in my first car. Then when it fit, I wrapped the box with cloth and resin. Worked great for a one-off. Not all that rigid unless it reinforced however.

[keyser]

Originally Posted by gedlee

About 30 years ago I taped together some boxes out of cardboard that just fit into a small and complex space in my first car. Then when it fit, I wrapped the box with cloth and resin. Worked great for a one-off. Not all that rigid unless it reinforced however.

Beautiful!

[heffree]

Gedlee - with the composite stuff you were doing, were you just doing layers of carbon composite or did you do sandwich structures with the honeycomb stuff? I was thinking of trying a sandwich structure that has polyurethane in the honeycomb.