leverage: was aftertouch

[Dennis Johnson]

        I did have a longwinded response to this ongoing discussion, but
fortunately I was struck with the good sense to start over. All I would
like to say is this:

        When it comes to understanding the difference in how touch is
perceived between the low and high leverage parts, I agree completely that
the essence probably is in the rate of acceleration. However, I am not so
sure that inertia is the proper term to explain differences in leverage.
Leverage is independent of inertia, but not of work, acceleration or
momentum.

        That element of the total sensory impression of all this work,
acceleration and inertia which cannot be accounted for with touch weight
measurements, is a quantity which must somehow be added to the touch
weight, however intuitively. Consequently, if the work is to be perceived
as equal, or reasonably equal, and one system implies greater work, than
ideal touch weights for each system will be different. In other words, low
leverage feels best with slightly less DW, IMHO. I am not able to prove a
nonlinear relationship between touch weight and the this total sensory
impression but if it is not non-linear, than certainly the low leverage
parts have a steeper curve. The position of key leads are another
significant role in this relationship. Is it only a coincidence that
Steinway positioned leads from the center for decades with low leverage
parts, but recently has changed lead position with the transition to high
leverage?

        It is my experience that the low leverage parts feel best when I
achieve about 49-50 DW (with good UW, of course) but the high leverage
needs a little more resistance and seems to feel better at 51-52 DW when
the leads are positioned from the center. A similar (but not equal)
resistance can also be achieved for high leverage with lower DW by
positioning the leads from the front. If anyone is critical of low leverage
parts based on unsatisfactory experience, you really need to play one with
49-50 DW and 25-26 UW.

        I do not necessarily expect agreement, but the basic point I wish
to emphasize, from my experience, is simple. When these two systems are
compared in this way, with appropriately different DW's, I sense that lower
leverage allows the player to feel a little more closely connected to the
hammer. Just today I am finishing a D with low leverage. I had to modifiy
the wippen heels, and seriously reduce weight, but the touch weight in the
tenor is 50 DW, and 30 UW with very little lead, -now that is quick.


Dennis Johnson
johnsond@stolaf.edu
St. Olaf College


        Long live this thread!