Hi Ed,
You make some important points. I am not advocating the 'early' drop
timimg. The extra weight of the 'early' rep lever, does impact ppp playing,
and is especially noticable when trying to control that end of the dynamic
range. 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. Ari Isacc had
me look into this, and after staring at the model for about 100 hours I came
to the following.
After the jack contacts the let-off button, the hammer is still being
lifted by the jack about 3/8ths of an inch, before escaping. In other words,
for the rep lever to be involved in ppp playing, and not the jack, the
pianist must stop the downward movement of the key at the point where these
buttons are contacted. Of coure that is O.K., but the distince would be
about 3/8 ths below the wire, plus the escapment ("let-off") distince, from
the top of the hammer to the wire, which is maybe 1/16 th.
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.
Friendly greetings from Dallas
Dan
on 9/10/01 8:33 AM, A440A@AOL.COM at A440A@AOL.COM wrote:
> Kevin wrote:
>
>>> There are a couple of regulation differences that are interesting.
>>> #1-Drop is set slightly early, and #2- jack height to rep lever height is
>>> set so that there is no winking. The distance (jack height to rep lever
>>> top) is subtle, so as not to cause a hammer line wave.
>>> I beleive the reasoning for the earlier than usual drop, is that there
>>> is a smoother feel if drop and let-off are spaced slightly.
>>> Also, I beleive their thinking is, an earlier drop allows a safety
>> net which insures a positive 'scrape' or contact by the jack, which would
> be
>>> reduced if the drop timing is later that the let-off timing. In other
>>> words, let the jack do it's job of lifting the hammer. Keep the spring
>>> loaded rep lever out of the picture.
>
> Greetings,
> The only problem here is that the loaded rep lever is NOT out of the
> picture. It is being compressed by the pressure of the finger on the key,
> and this compression begins at the very last bit of control the pianist may
> want to exert in the softest passages.
> The combination of drop button contact and jack tender contact may or may
> not be exactly the same, that depends on a lot of geometry and dimensions
> being perfect. Staggering the contact times, like we do on the ranks on a
> harpsichord, lessens the apparent effect, but is no reason to increase the
> distance of drop.
>
> You can play a note on a grand piano very softly without the jack in
> place. The rep lever will usually carry the hammer up if there is any
> positive force from the spring. Imagine that on the softest note the pianist
> can play, that the weight of the hammer is carried by the rep lever. The
> friction of the jack against the knuckle is going to be virtually nil, and
> upon reaching let-off, the only resistance to the key will be the spring
> acting against the drop button on one end, and acting against the let-off
> button on the other,(via the jack tender). This allows the jack to be
> touching the leather, which I consider important, but on pianissimo play, the
> pianist has a very fine control, not needing to get through let-off with an
> early spring in play. These things contribute to what I call "transparent
> escapement".
> My personal set-up is to have the fastest spring possible without it
> being felt in the key,(any more is a waste, since it doesn't apprecialby
> increase the key return speed in fast repetition), the slightest contact
> between jack and knuckle that I can feel with my finger on the tender, and
> the let-off and drop both set at the same distance to the string. I
> determine this distance by the requirements of the job. On the concert stage
> and the studios, the distance is as close as possible to the maximum
> excursion of the string. In the homes, where durability is a consideration,
> slightly more.
> Regards,
> Ed Foote RPT
>
>
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