It is possible to shim a harpsichord soundboard, but the cracks are probably more of a cosmetic problem than an acoustic problem.
I would not be in a hurry to assume the tuning instability was caused by the cracked soundboard.
My first guess would be that the tuning instability and the wide cracks were caused by low humidity.
I would also want to check very carefully for structural instability in the treble cheek and soundboard.
See if the gap is closing and binding the registers.
School music departments often have no idea how to care for a harpsichord.
A college in Louisiana ruined a Sutherland harpsichord because they had no understanding of the effects of close spotlights on a harpsichord tuning.
When I tuned for the Charlotte symphony I tuned 90 minutes before each use of the harpsichord, monitoring for constant pitch drift as the heat was off and on, causing a fine instrument to drift 20 cents overnight.
My harpsichord has two small DampChaser rods and a humidistat inside the instrument, which helps limit the reaction to humidity change.
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Ed Sutton
ed440@me.com(980) 254-7413
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Original Message:
Sent: 11-18-2022 10:49
From: Barbara Richmond
Subject: Z-box soundboard
Hi everyone,
I was tuning the piano in a high school choir room, when I saw this harpsichord. I asked the choir director about it. There was a story! Anyway, someone did some work, it doesn't stay in tune. I didn't have time to really look, but snapped this picture of the worst of it. Does one ever shim a harpsichord soundboard? I haven't considered it before, maybe because I've never seen one in such a state.
Thanks,
Barb Richmond
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Barbara Richmond, RPT
Bloomington, Illinois
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