[CAUT] Weikert felt; was 80 year old S&S hammers

[Don Mannino]

Fred, you are 'restoring balance to the force' on so many fronts! :-)

I would have to say that carrying this concept into soundboard and scale
is where it may not be held up by the empirical evidence.  I agree with
these ideas in regard to hammer design / action ratio and tone, and
certainly good hammer pressing and great felt is so important.

Where the flexible board / low tension scale relationship to this breaks
down, for me, is to consider the old Mason & Hamlin pianos.  Correct me
if I'm wrong ye bellymen, but my understanding is that those pianos had
rather thick and stiff soundboards, and what we all love about them is
their singing quality and expressive nature.  It was a different
approach than Steinway, and may have kept them out of the concert hall
to a large degree, but they were beautiful, expressive pianos.

It is also possible to make a light and flexible board with a higher
tension scale, and match them through very careful setting of a light
downbearing load. So there are more variables to the design process than
just a simple dichotomy of "high tension / stiff board" vs. "low tension
/ flexible board."

I have quite a few recordings of Steinway (mostly) pianos from 1920s
forward. Although it is hard to be absolute in judging the tone because
of the recording technology (and later editing process to remove noise),
I do not find that the sound of the big concert pianos differs much from
those modern pianos which are well voiced. I am sure there were loud
bombastic concerto pianos then, as well as more expressive recital and
home pianos. But it is also clear that the Steinway family saw the
benefits of lower tension and lighter softer hammers in their home
pianos (modem M, especially).

I don't mean to turn this into a piano comparison discussion, so please
change the subject if you want to continue in that direction.  I want to
say, though, that it has been Kawai America's desire for the Shigeru
Kawai pianos to have these characteristics in the smaller models.  An
SK-2 or SK-3 that is voiced as I like it has very soft hammers that give
a good range of tone.  The Japanese tend to not like this voicing, so
the pianos often don't arrive voiced this way.  But over time, those
with the best hammers and voicing remain the best sounding pianos.

So, for me good sustain and expressive tone go together, and these come
from the right hammers and soundboard design.  I think good impedance
matching of the board with the string scale is important for this, no
matter what the overall tension level might be. 

Now, as to pre-1900 pianos, I also agree that these can be beautiful and
expressive instruments in a very different way from modern pianos.  When
I play them, though, my thoroughly modern ear misses the sustain mostly.

Don Mannino
  

-----Original Message-----
From: caut-bounces at ptg.org [mailto:caut-bounces at ptg.org] On Behalf Of
Fred Sturm
Sent: Thursday, April 16, 2009 6:52 AM
To: caut University Technicians
Subject: Re: [CAUT] Weikert felt; was 80 year old S&S hammers

A lighter weight hammer will rebound more quickly, hence will damp less
upper partials while dwelling on the string. (It will be "brighter" than
an otherwise equal heavier hammer).

A softer hammer will dwell longer on the string, hence will produce less
upper partials. (It will be "darker" than an otherwise equal harder
hammer).

Hammer felt compresses (non-linearly - meaning the hardness curve
becomes steeper the more rapid the impact), so a hammer that hits a
string faster will produce more high partials.

High ratio action is conducive to more rapid acceleration of a hammer
(assuming appropriate mass), hence you can get more speed more easily,
hence more high partials at "full force" and a larger range of
difference, easier to achieve (difference in partial mixes along a
spectrum of force applied to the key).
	
Taking this together, a softer hammer with a higher ratio can probably
produce a greater range of tone quality. It needs to be lighter as well,
for logistical reasons (amount of mass a finger can readily accelerate
at that ratio). The lighter hammer will also be brighter by nature
(other things equal).

It seems from experience that heavier systems (thicker boards and
ribs) need heavier hammers to drive them and achieve power, and that
they need harder hammers to achieve high partial mixes (perceived
loudness, ability to penetrate and be heard through other sound, whether
from the rest of the piano or other instruments).

It also seems from experience that softer hammers sound brighter on
lighter systems.

	Combining these things, it seems logical that for a lighter,
more responsive board, a lighter, softer hammer with a higher ratio
would make for a good match. I am speculating that lighter plus higher
ratio would give an "easier expressive range" to the pianist. This is
based partly on experience with some older instruments, and trying to
make sense of what I experience.
	
	In any case, you need to have enough mass to drive whatever
belly assembly you have. Then you can think about what ratio is most
appropriate for that mass. And I should add that I am not really
advocating for one thing over another. Rather, I am advocating for
having a range of choices.
Regards,
Fred Sturm
University of New Mexico
fssturm at unm.edu