Key Leads and Inertia

[John Hartman]

Stephen Birkett wrote:

>
> One factor that does have a serious impact on all of this is the mass of 
> the dampers, all the more so because it is relatively far away from the 
> fulcrum. These do seem to be treated in rather cavalier fashion in 
> discussions of key balancing [it never seems to be made explicitly clear 
> whether the dampers are on or off when doing measurements, like a balck 
> sheep relative in jail who never gets mentioned in polite company]. The 
> *inertial* effects of dampers being lifted vs pedal up are certainly 
> quite significant. Again you can feel this in playing. Why do you 
> suppose most modern pianists habitually keep the pedal down? Hmmmm.


Stephen,

Thanks for bringing this up, it's another reason to be suspicious of the 
benefits of precision static calibration. It strikes me as absurd to 
worry about small discrepancies in static balance weight from note to 
note with the damper action disconnected. This means that all of the 
effort taken to get the action even is wasted if the pianist plays with 
the pedal down. Another thing that is usually disregarded is the fact 
that the front arm of the key is a variable target. For convenience we 
measure the key input out near the end were we use our weights to 
measure down and up weights. This is not how the piano is played - the 
whole exposed surfaces of the keys are used. What does this do to a 
carefully calibrated action's balance and leverage?

What we need to do is convince pianist to firmly press the right pedal 
and keep it down while playing. In addition they should keep the tips of 
there fingers precisely 9 mm from the ends of the keys. This is the only 
way that pianist can experience the full benefits of a precision 
balanced action. Oh, I forgot, they should only play very softly.

John Hartman RPT

John Hartman Pianos
[link redacted at request of site owner - Jul 25, 2015]
Rebuilding Steinway and Mason & Hamlin
Grand Pianos Since 1979

Piano Technicians Journal
Journal Illustrator/Contributing Editor
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