measuring key weight ratio

Jenneetah yardbird@vermontel.net
Thu, 23 Sep 2004 08:28:59 -0400


At 9:04 AM +0100 9/23/04, Richard Brekne wrote:
>Put 20 grams on the front of the key, zero your scale, and then put 
>the 10 grams on the capstan !!
>Dont feel silly... many of us have stumbled on this one too.

The only part of this which gets complicated is getting the front 
weight on a back-weighted key. The value of FW as a measure of key 
balance is that the front weight we read is how much heavier the 
front half of the key than the back half. As long as that back half 
is uniform, that net positive weight of the front has meaning. And it 
is quite uniform, as David Stanwood quickly found out in his early 
explorations, not only within keyboards but across many different 
piano lengths.

As soon as someone installs back leads, this predictable uniformity 
is upset, which is why, when doing a action survey, back leads have 
to be temporarily removed. But as David Love observed, this is not an 
issue in reading key ratio.

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