Trapezoidal keyboard and magic line

Isaac OLEG oleg-i@wanadoo.fr
Sat, 8 Mar 2003 12:53:28 +0100


A geometry question :

I wonder what happen to the magic line on instruments with a
trapezoidal keyboard, as S&S mod D.

Seems to me that the bass side of the whippen axe may be lower if we
want to stay consistent with the magic line.
I've seen a larger spread on the bass side on some instruments
(shimmed flanges), that may go in that direction too. I've noticed too
higher key height on the bass side (more cardboard punching under the
front too) a correction for too heavy basses problem.

Makes sense to me that the shorter length of the segment in the treble
, assuming the whippen heel is at the same place all along the action,
mean that the whippen axe may change height to respect the optimum
alignment.

Do some have some thoughts about that ?

It is possibly an undocumented and unofficial way to have the tubular
frame in a slant (not twisted , but different height ).

My friend Stephen Paulello used a whippen heel that can be height
adjusted to compensate for that in his grand piano, you should see the
evenness of the hammer rise all along the instrument !

Best

Isaac OLEG

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