Shigeru Kawai regulation

[thepianoarts]

Hi Ed,

    I am still studying your sugestion that playing off the rep lever is
possible. Yes, I am sure without a jack the piano will play...
    But, with a jack, and with a typical regulation as far as drop and
let-off timing goes, I think in a repeated note, or the first blow, that the
rep lever cannot be released low enough to fire the hammer, without the help
of the jack.  I tried on two field grands to play 'off the rep lever', and
was not able to do so. I had to release the key so as to get the jack back
under the knuckle, in order to fire the key. Again, we are talking about
shallow, and/or low volosity, repeated, slow or fast  ppp playing.
   I got to thinking, after reading your post, that this procedure is
related to a repeated note, and not the 'first' blow.  So, the spring
tension must be fairly stout, yes? And the pinning at the rep lever
snug...and the drop late-ish, and let-off close, and the hammer flange
pinning not too tight...
How do you set up an action so I can try and duplicate this?

PS  Could these pianists who claim to be playing off the rep lever, actually
be "bumping" the hammer up, off of the jack top?  In other words, the key
energy is cut off short,and the jack does not go through let-off?

 
Dan

on 9/10/01 10:23 AM, A440A@AOL.COM at A440A@AOL.COM wrote:

> Dan writes; 
> <<On the other hand, I do not concure with the idea that the rep lever
> can be thought of as contributing to control in ppp playing. <<
> 
> Ok,  but I just took the jack out of a whippen and I can still play the
> notes, some surprisingly louder than I thought.  And this is not with an
> overly strong spring!  My main point was that properly set, the balancier(rep
> lever) can create virtually a frictionless escapement under ppp playing.
> 
> 
>>> When drop screw and let-off button are touched at the same time, I beleive
> the following are true, and support the contention that the pianist is not
> 'playing off of the rep lever'.
> 
> 1- The hammer is 3/8 ths plus 1/16 th. from the wire( depending on the
> condition of the knuckle)
> 2- The rep lever is spring loaded, a poor canidate for lifting the hammer
> 3- The direction of movement of the rep lever after touching the drop button
> is horizontal, not vertical.>>
> 
> Inre #3.  The balancier's direction of movement doesn't become
> horizontal, but is still upward. What changes is the point of rotation.
> Before contact with the drop screw, the balancier's contact point with the
> knuckle is rotating on a radius from the whippen centerpin.  Upon contact,
> its center of rotation shifts to the dropbutton contact point, at which time
> the radius begins to be described by the balancier's centerpin, still being
> lifted by the key.  This represents a major change in moment arm, but not a
> change in direction from vertical to horizontal,( at least, that's the way it
> looks to me.  
> To use your figures of 3/8" engagement and 1/16" escapement, that means
> that for the 5/16" prior to let-off, the balancier is still in contact with
> the knuckle.  It is during this period that the balancier can reduce the
> friction between the knuckle and the jack for ppp play.  The distance over
> which the friction can be lessened is also dependant on where the jack sits
> under the knuckle.
> I still champion  minimizing the amount of jack travel (by bringing it as
> far proximal as performance allows), setting the spring to its least positive
> strength, and setting let-off and drop at the same distance.  I think this
> allows the least resistance to the softest play.  Once done like this, you
> can take the jack out and the note will still play the same at ppp.
> This is ONE reason, I keep my balancier as high as I can. The other is
> simply to reduce the total amount of work that the pianist's fingers must do
> in the course of a lot of play. When you consider that some of the serious
> classical people spend four hours a day playing, the grams add up.
> Regards, 
> Ed Foote RPT