Optimizing repetition

[Joel Rappaport]

I mentioned, specifically for Alicia deLarrocha,
>  the thing to notice is that she wants the repetition down at the
>  ***bottom*** of the key travel.

and Richard Moody asked,
> Does that mean after touch at (near) the bottom of the key stroke?
> And does she want the damper down before she repeats?

as usual, Jim Coleman, Sr. improved the accuracy of my comment by
observing,
> I'm sure Joel meant "NEAR the bottom of the stroke."

I guess I should have described it as a lawyer would: "At or about the
bottom of the key travel."  And after touch isn't really the thing about
which she is fastidious.  After touch has a beginning, length and end
which is another subject completely.  My point is that she demands that
the action repeat with the key having to rise from "bottoming out" as
little as possible.  And no, she is going so fast, she does not require
the damper to get back on the string before the next blow.

Regarding center pin friction, Bob Davis observed,
> Greater friction in the hammer flange and (especially) repetition lever
> centers causes (or allows) the spring to be set tighter for the same
> rise ate, which causes the jack to fly back under the knuckle sooner,
> increasing repetition speed.

Of course, it depends on how fine a degree of tightness Bob is thinking
about here, but in general, I find that greater friction in any of those
action centers is death to repetition.  Just a shade too much friction
in the hammer flange will prevent fast repetition.  It would be better
to check the jack pinning and ream that bushing for better speed there
than try to increase friction at (or leave sluggish) the hammer flange
pinning.

Newton Hunt also pointed out, and rightfully so, that the repetition
lever pinning has to be within parameters:
> I would check the rep lever pinning.  There should be some risistence
> here.  If there is none the spring is weakened to compensate and not
> quite enough to assist repitition.

But again, Newton most likely (he'd have to speak for himself) would not
advocate excessive friction in the rep lever just so the spring would be
strengthened.

Fred has presented an excellent check list of concert preparation for
the action and I might add just a couple of points:

FSSturm@aol.com wrote:
>
> So as not to begin from absolute scratch, let's assume fairly standard
> condition and regulation. Letoff closer to 1/32" than 1/16". Drop about
> 3/32". Check near as close as it can be without tail rubbing on
> backcheck when the hammer movement is resisted by one hand while the
> other presses down the key.

Yes, this is not a normal regulation specification, but good practice to
set the check as high as possible without the hammer tails rubbing.  Be
sure to press firmly down on the hammer when testing to simulate the
hammer's movement on a very hard blow.

> Hammertail rough enough to check except on the softest pianissimo
> blow (that perennial Steinway struggle between repetition spring
> tension and tail/check distance). Repetition spring strong enough to
> raise the hammer smoothly and rapidly (without hesitation) when
> released from check, though not enough to jerk or bounce.

I like to say that the spring strength is "just this side" of feeling
the  release through the key.

> Repetition lever set so that when you trip the
> jack tender lightly with a finger, you can just feel the resistance of
> the knuckle (friction), but the jack returns reliably all the way
> without hanging up when released slowly by the finger. Jack position
> set to line up with knuckle molding (and doesn't trip when you impede
> the movement of the hammer).

Now here is something you might try.  It is a little difficult to
explain why this works, but keep in mind, someone like deLarrocha will
be playing, not you or me.  Set the back edge of the jack slightly (at
or about slightly, so Jim Coleman doesn't have to come to my rescue
again) behind the knuckle wood instead of directly lined up with the
rear edge.  That is, the jack at rest is a lttle more away from the
player than we normally think it should be.  The variation is not so
much that the jack doesn't perform as normal and it will pass all the
above tests.  Assume all else is equal and the jack will be moving the
exact same distance as it would with the normal adjustment specs.  But
after it is tripped, it winds up a little closer to the knucle than
normal and is just a little more ready for the next repetition.  I am
not trying to change the standard specifications for regulation with
this tip.  It just works well when preparing a grand action for someone
who likes super fast repetition.

> Blow distance, key dip, aftertouch set to fairly standard
> measurements and relationships to one another - in the range of 1 7/8",
> 3/8"+, .050". Action centers free (no sluggishness). Knuckles brushed,
> Teflon powdered, firm and round. Key bushings almost friction free.
>
Hope this helps.  To answer another question raised, she has played both
Hamburg and New York Steinways when we have worked with her.

Joel Rappaport
Round Rock, Texas