What does the moi feel like?

[John Hartman]

Ed Sutton wrote:
>
> Could I make or buy a gauge to measure this? 
>  
> Does this line of thought seem useful in understanding the situation?
>  
> For example, has anyone felt a key such as I describe?
>  

Ed, just some speculations:

This reminds me of simple physics problem; how to find the mass of an 
object in outer space. The solution is to use a device that measures 
inertia instead of weight. One of the ways to do this is with a tray 
that is attached to springs. secure the object in the tray and set it 
into harmonic motion. Measure the period and you can find the mass.

I expect that we don't naturally feel the weight of inertia since we 
have gravity to help up asses the mass of objects when ever we need to. 
Ask someone to sense the weight of an object and they will heft it up 
and down in their hand feeling the pull of gravity. I expect we are not 
inclined to sense the mass (inertia) of the action when we play the 
piano. That's why I don't put too much credit in the statements about 
heavy or light actions.

Even though we can't asses the inertia of the action by feel we do pay a 
price for it. If it is too much we will feel fatigued wile playing and 
the action and our joints will ware out sooner. Playing fast passages 
will be difficult and repetition will suffer. If it too little the 
player will not be able to express a full range of dynamics.

If it were possible we could make something that would measure the 
inertia of the piano as it is played by measuring the contact force 
between the fingers and the key. The interaction between the tips of the 
fingers and the keys should indicate the amount of force used to move 
the key and if this information were combined with the tonal output it 
would show, roughly what the inertia is. Funny thing is we have such a 
devise, our sense of touch and hearing. But it just doesn't work for us. 
I suspect the reason for this is that we can't discern between the touch 
when our finger is moving the key through the stroke and when it is 
contacting the front rail punching. We sense both at once and this only 
reflects the total force the pianist is using.


John Hartman RPT

John Hartman Pianos
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Rebuilding Steinway and Mason & Hamlin
Grand Pianos Since 1979

Piano Technicians Journal
Journal Illustrator/Contributing Editor
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