Aftertouch evaluation

[Richard Brekne]

Bob Hull wrote:

> I am wondering about the value of different methods of evaluating
> aftertouch on a grand. I know one method is to add punchings on top of
> those on the front rail pin until let-off can't take place;
>
> Another method I've heard of and used is to look at the final position
> of the jack in relationship to the knuckle and jack cushion after drop
> - but this can't be done with the action in the piano;  The next
> method (which I don't think I've read about anywhere) is my question
> to the list:  Can you accurately evaluate aftertouch by traveling the
> key/hammer through drop and then moving the jack tender downward to
> see how far the jack travels before being stopped by the jack cushion?
>
>

I suppose you could.... but seems like a lot of effort for return. If
you start with a perfectly adjusted let off and drop, which is to say
the jack tender and drop screw engage nearly exactly at the same time
with the jack just a rats hair (and no more) ahead of the drop screw,
then you know whatever you are feeling beyond that spot is aftertouch.
It need be no more then enough to clear the jack top from the knuckle,
and can be no more then what will bury the jack in the cushion. Anything
in between is really in the acceptable range. So the point is to get
something that is consitant and feels good. All this can be done by feel
really. And its feel that the pianists are concerned with.


> Also, if you are using the addition of punchings on the front rail pin
> until let-off fails, what are some good parameters to stay within for
> "good" aftertouch, i.e. .050 - .060 ?  I know the Steinway manual says
> that a good amount is about the thickness of a new penny.  How far can
> we stray from that measurement and still be alright?
>
> Bob

Cheers
RicB

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