Ed,
I learned that trick by accident. A pianist complained about the thunk upon release of her una corda pedal. I didn't find the thunk atypical. Confounded, I spotted an old piece of damper felt in my case, so I pulverized it and dropped it down the crack to see if it might help which it did. I couldn't see any change in string alignment and the piano sounded about the same to me.
Later I met the pianist in the hall and our conversation went about like this,
Pianist: Thanks for fixing that thunk and also voicing my piano, it sounds great!!
Me: ... uh ... duh... well....Oh yes!, I'm glad you like it.
> ----------
> From: Ed Sutton
> Reply To: College and University Technicians
> Sent: Thursday, September 18, 2003 9:46 AM
> To: College and University Technicians
> Subject: Re: performance piano - student psychopathology 101
>
> This is similar to putting index cards between the left stop block and the key
> frame.
>
> Are you and I the only technicians doing this? Maybe recording studio technicians?
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