Strange buzz musings

[J Patrick Draine]

Dear List:
A couple months ago I queried the list for help in diagnosing an
intermittent buzz in a Steinway B. While that piano presently seems to be
behaving, I have (occasionally -- over the past 20 years) continued to
encounter mystery buzzes in a few other pianos.
One smiles with relief upon finding a penny, screw, or shard of glass lying
on the soundboard; upon its removal the ugly sounds have disappeared.
You're a hero! But when one can find no debris, soundboard cracks, rib
seperations, loose screws, rattly lamps, etc. and the ugly sound is still
there, one feels incompetent in front of the client, and with yet another
anxiety to lose sleep over.
Has anyone developed a flow chart approach to this multi-variant problem
("Step A: Look for visible stuff on the soundboard. Step B ... Step Q: Bill
the client for the time elapsed, start driving home ((be sure there are
some brews in the fridge)) ...")? Does a stethosope help?

Frustrated,

Patrick Draine