Fw: Patent Notice

[Richard Brekne]

Bill Ballard wrote:

> >What I am beginning to think is that the original designs with slightly
> >higher action ratios (6.0 - 6.1) delivered something that the more modern
> >trend of 5.5 or lower cannot, that there is something inherent in the
> >relationship between key and hammer movement that is critical in imparting a
> >sense of control.  While this necessitates relatively low strike weights (by
> >today's standards), I am more and more inclined to think that this dilemma
> >represents the Sophie's choice of action design.
>
> Again, agreed. Action ratios amplify the angular motion of the key,
> and higher ratios provide for more gradations of hammer shank angular
> motion per incremental-unit-of-individual-pianist's-key-motion.
> Remember that in the formula for the force delivered to the string by
> the hammer (F=m*a), it's the acceleration which is the pianist's
> variable factor. Adjust the formula for lower SW and higher
> acceleration (by bumping the leverage up), and you've increased the
> portion of the transaction in which the pianist's input has an
> effect. More control for the pianist.
>

I have serious trouble with this line of reasoning that seems to claim more
control for higher action ratios and uses the Force equation removed from all
actual playing contexts to justify it. While it is true that ratios amplify the
angular motion (distance) of the key as you describe, it is also true that they
amplify (as long as you choose that word) the weight relationships of the system
in the opposite sense. While you get more hammer movement for key movement with a
higher ratio, the hammer takes more input force to move, which requires of the
pianist to make use of that higher acceration to achieve the same level of sound.
This effect is exasperated by fact that to achieve similar BW one needs less
massive hammers. The end result is that the dynamic range of sound volume is
effectively narrowed, because on the one hand you cant get as much sound out of
the high ratio system to begin with, and on the other hand you cannot control the
same level of ppp to the same degree due too exactly the increased accelleration
the system provides.

A pianist not only moves his / her fingers X amount of distance, he/she uses X
amount of finger power in expectation of X amount of acoustic response from the
instrument.  The speed of the hammer relative to the speed of the key is very
much in the picture, probably most easily noticed during slow expressive passages
or at very low ppp levels, with the greatest level of control being a function of
being able to control the slowest possible hammer blow. High action ratios do not
provide this, they speed up the hammers travel relative to the key speed. And if
they didnt... they'd be hoplessly useless.

In order to get the same tone profile with a light hammer / high ratio system you
need to use more finger power then if you use a heavy hammer / low ratio system
(assuming same BW). There are two obvious reasons for this more hammer mass and
more leverage. Then on the flip side of that same acceleration coin, is that one
is actually able to play slower and softer because of exactly the slower hammer
speed for equal key speed.

To underscore all this let me share with you something all this discussion this
past week led me to do.

I just completed an experiment today with two Hamburg C's. One has a top middle
SW curve with a 5.6 ratio, BW on average of 40 and FW's on that Maximums table we
all talk about so much. The other has a factory half medium with a roughly 6.0
ratio and factory FW's... BW on average of 38 but varies +/- 4 grams in places. I
askec 12 of our piano majors today to sit and tell me which piano gave them most
control at soft play. I gave them no hints, no indications of what I wanted to
hear. All 12 picked the piano with the 5.6 ratio. Then I asked them to sit in the
back of the room while one of them played first one, then the other with similiar
passages. They were asked which piano they prefered and why. The response was not
only unanimous, but it was emphatic as well. Again the 5.6 ratio piano was
picked. When asked to discuss why they felt the one was better then the other
they dropped comments like more power, and more body. Roundness and increased
tonal color were mentioned several times. And interesting enough... (tho I am not
suprised by this anymore) they also without exception said they felt the piano
with the lower ratio and higher BW was actually lighter. And I am not even
finished with the final regulation on this instrument after the Hammer change and
SW increase. Both are voiced in my me (read similar voicing technique) within the
past 2 weeks.


Cheers.


Richard Brekne
RPT, N.P.T.F.
UiB, Bergen, Norway
mailto:rbrekne@broadpark.no
http://home.broadpark.no/~rbrekne/ricmain.html