Posted by Klaus on January 10, 2001 at 12:24:12:
In Reply to: A worrisome noise posted by Benjamin Schardt on January 10, 2001 at 11:29:47:
Once had a somewhat similar experience with a trombone. During a church concert there was a hard snapping sound close to my left ear. After that Ab played in seventh position went on singing after air supply stopped. The instrument was still under guarantee, so I got a new bell.
The diagnosis was a ridge broken up in an invisible inner soldering in a stay.
From your reporting I would suggest a closer look at all solderings at the bell: leadpipe, stays, guards, and the rolled bell flare, where the soldering of the inner wire might be partlially broken.
Klaus