Key Leads and Inertia

[David C. Stanwood]

Brekne wrote:

>Would be fun to see this instrument. The thing about springs and magnets is
>that the farther into the stroke you get the weaker their effect. This is
>supposed to be a bad thing according to some critics.

Just to reiterate the little experiment I did last week.  The spring I
tested gave up a gram to a gram and a half force at the front of the key
from top to bottom of stroke..  This force is the same even when the key is
being played and the dynamic force being applied is in hundreds of grams...
so I'd say the detrimental effect of changing spring force is in the minds
of the critics.  The magnet thing is more interesting.  The gaps of the
opposing back magnets and the attracting front magnets may be set in
various ways so that the force is more at the top - less at the bottom,
less at the top - more at the bottom, etc...  but again these subtle
differences are lost in din of dynamic playing force... 

Here is a picture of setting the magnet gaps in the first Simplified Magnet
Action being installed by Stanwood/Pietjouw in Holland at the inventors
workshop.  The installation pictured shows magnets used in conjunction with
keyleads.

http://www.stanwoodpiano.com/magset1.jpg

David Stanwood