Hand-Held Megaphones: Rubber ring around edge of Horn

Or do you mean a rubber acoustic barrier between the speaker part and the microphone part, to avoid microphony?

N_Cook:

See that black thing on the edge of the widest part of the megaphone?

That is what I'm referring to.

I suspect it has a major effect in damping the high-Q mechanical resonances of the cone, and so improving the sound quality.

I am sure it does affect the sound, but in a very small way. If you did it with alot large horn and an audiophile driver in it, I am sure the "golden ear" crowd could tell the difference.

The way to test it would be a short burst tone and a scope to read the ringing. Or perhaps a square wave and you watch the leading edges. Or course it might only be difference of 8 cycles versus ten cycles.

It would reduce ringing in the metal or fibreglass 'bell' of the horn. Just tap the horn and listen to the 'clang' sound with and without the ring.

-- ~ Adrian Tuddenham ~ (Remove the ".invalid"s and add ".co.uk" to reply)

It would only affect top frequency by diffraction. With a good flaring of the mouth, might not do anything with the sharp edge. These things don't have very good highs to begin with.

Greg

GS wrote: "- show quoted text - It would only affect top frequency by diffraction. With a good flaring of the mouth, might not do anything with the sharp edge. These things don't have very good highs to begin with.

Greg "

^^ The BEST explanation by far!! And that diagram I glimpsed a long time ago alluded to this. Thanks.