My sphere in cube idea for reducing standing waves

[mcmahon48]

The best shape for a speaker container would be a sphere, which is difficult to be easily reproduced by a diyer, but with new technology it can be simply done. Make a cubical shape container, example 4 x 4 x 4, buy a 4 inch rubber ball that can be deflated. Spray the rubber ball with cooking oil all over insert the inflated ball that snuggly fits in the cube. Clamp a temporary baffle that has two holes drilled in opposite corners and spray the side that is facing the open part where the ball is located. Clamp the temporary baffle down and the spray in the neat part of this the self sealing insulating foam sold at hardware stores. Following direction for the amount of time needed to let it set and harden. Later remove temporary baffle, deflate the ball and remove. No more standing waves and better response.

[mondogenerator]

Originally Posted by mcmahon48

The best shape for a speaker container would be a sphere, which is difficult to be easily reproduced by a diyer, but with new technology it can be simply done. Make a cubical shape container, example 4 x 4 x 4, buy a 4 inch rubber ball that can be deflated. Spray the rubber ball with cooking oil all over insert the inflated ball that snuggly fits in the cube. Clamp a temporary baffle that has two holes drilled in opposite corners and spray the side that is facing the open part where the ball is located. Clamp the temporary baffle down and the spray in the neat part of this the self sealing insulating foam sold at hardware stores. Following direction for the amount of time needed to let it set and harden. Later remove temporary baffle, deflate the ball and remove. No more standing waves and better response.

REDUCE standing waves???? reduce to one frequency in ALL directions maybe but not reduce them in amplitude--IMHO BAD BAD idea

[PeteMcK]

how about a hemisphere?

[LineSource]

Originally Posted by mcmahon48

The best shape for a speaker container would be a sphere, ...

I think B&W research on spherical enclosures with tapered tube rear wave absorption is one of the best midrange and tweeter designs. The B&W website has technical information and measurements.

A friend took large styrofoam shapes - sphere + cone - cut them to mimic the B&W shape, sealed them with primer paint, and hand coated this shape with sand-only cement plus fiberglass string mat. When it had hardened he used acetone to melt away the styrofoam. The midrange sound was excellent.


Tony Gee produced a similar shape in his Galactica speaker by stacking MDF cut outs.

The Lumen White Light speaker uses a bulge+taper in a more traditional cabinet claiming it removes the reqirement for (any? most?) stuffing