Inertia, was "Grand Touch"

[ed440 at mindspring.com]

Jude-

The mathematics of the key lead inertia is so exciting, it's hard to believe it may not be significant. I believe one fellow built a 10 foot key model to demonstrate this. Unfortunately he left out the rest of the piano, which might have given different results.

A fairly good test would be to modify a piano with approximately half the keys with leads at the front and half with leads near the balance rail, randomly distributed.

Then have many pianists play many pieces on the piano and report if they have problems with any particular notes: "G#4 hard to trill; poor staccato on D3" etc.  Or maybe have them do Hanon exercises so every key gets equal use.

Meanwhile, don't forget that the pianist is part of the system, and they come with a wide array of different sized levers and weights, not to mention techniques, so be sure to include an interesting sampling of pianists!

Finally, as Ed Foote mentioned in a recent post, hammer voicing influences the pianists experience of effort required to produce a desired dynamic contrast, so do it all over again with soft, medium and hard hammers.

Then summarize everything into one simple, unambiguous all purpose sentence! ;-)

But seriously, you were not far off from a chance to run this experiment.  Maybe someday, someone will do it.  It wouldn't surprise me to hear that some folks named Kawai may have already done it, but they probably aren't telling.

Ed Sutton
-----Original Message-----
>From: Absolute Piano <absolutepiano at comcast.net>
>Sent: Jul 12, 2006 11:02 PM
>To: Pianotech List <pianotech at ptg.org>
>Subject: Re: Inertia, was "Grand Touch"
>
>Thanks Vladan and all for all the info.
>
>There is a lot to chew on. My interest is in the practical application. Why 
>is it that two keys with the same balance weight and the same front weight 
>but leads arranged differently seem to me to feel the same?
>
>I ask because I had a customer that asked me to place all the leads closer 
>to the front and to use less leads after I had already set up the FW to my 
>specification in a new keyboard using a tower pattern nice and close to the 
>balance rail. I went through all the trouble but as far as I or anyone else 
>could tell the action felt the same.
>
>I'm in the process of building several action models to test the science as 
>I am slowly digesting it so you are all being quite helpful. Unfortunately 
>with reality hanging over me it may take awhile to report back any results.
>
>Best,
>
>Jude Reveley, RPT
>Absolute Piano Restoration, LLC
>Boston, Massachusetts 
>
>