Evidence of overlacquered hammers

[Bernhard Stopper]

I agree that different pianos need different hammers...
but in my opinion this is more affected by the scale than by the soundboard.
Surely a high tension scale requires also a thicker soundboard  (but mainly
for static reasons in my opinion) and a low tension scale a thinner one.
A high tension scale (like a Bösendorfer) works better with a heavier and
denser hammer than a low tension scale like the Steinway. A high tension
scale has a higher stiffness at the strike point and throws a same hammer
faster back than on a low tension scale. So a light hammer on a high tension
scale would produce too much overtones. This can corrected in some way by
voicing. But its still better to choose an appropriate hammer for a specific
scale, so that less voicing is necessary.

A too heavy hammer on a low tension scale does not overdrive the soundboard,
but can overdrive the string. A string can act as linear spring in a
specific range. If this range is overdriven by a too heavy hammer, the
string blocks like a wall and produce distortion.

The time, the hammer is in contact with the string is the main effect of how
many partials and in what weight they will occur. The soundboard
itself has absolutely no possibiliy to add any partials to the strings
spectrum (except the short shock spectrum caused by the hammer impact) and
acts only as an amplifier and filter. But the oscillator is the string.

best regards

Bernhard Stopper


David Love wrote:

> The evidence of different soundboards (and soundboards in various
> conditions) needing hammers of varying densities is so abundant in the
> piano circles that I run in that I don't even know what to say to those
> who are interested in this possibility except try it for yourself and
> see.  You wouldn't put a very hard Renner hammer designed for a
> Boesendorfer on a piano that would sound best with a Ronsen soft Bacon
> felt hammer--and there are many such examples out there.  ........