Tweeter diaphram question

[Mr. RF62]

Hey all,

I have recently received (scored?) a pair of Tannoy Berkeley speakers and am having an issue with one of the tweeters. I took it apart and the diaphram's voice coil sits in a gap suspended by some shims. It is a concentric speaker.

Question: Does the voice coil have to have NO contact (needs to float) in the gap where it sits? And if it does come into contact with the sides, will it cut out?

Thanks

[Guest " "]

not familiar with the tannoys, but all driver voice coils float...exception are the ones in fero-fluid. when a coil which is intended to float begins to rub a side wall you will get distortion and eventually the rubbing will wear down the windings and create an open circut.

[Mr. RF62]

Thanks sf. The problem I was having was it would only play if I cranked the volume. So when I opened it up, it looked like some metal shavings got in the V.C. gap. So I blew some compressed air in there to rid that and tried to shuffle the shims so that there was no connection between the V.C. and the sides. It was working more consistantly last I listened, but need more time to test.

[djk]

NEVER use compressed air to try and clean the magnetic gap, it drives the particles under the top-plate and they work themselves back over time with usage

Do use triangles folded of masking tape (sticky-side out), it can take hours to get the gap clean..

Try cleaning the switches on the network if the driver cuts out again, rotate them about 100 times first.

The Cheviot was my favorite Tannoy model (as a former dealer).

[Mr. RF62]

Thanks djk, when it happens again I'll know what to do.