Singing rims

[Horace Greeley]

At 09:10 AM 2/5/96 -0700, you wrote:
>> When
>>I went over to the long side of the case and lightly rested my fingers on
>>it, I could feel the entire case vibrating from just that one string! Even
>>though that was 20-25 years ago, I can still remember the feeling of awe
>>I experienced as I listened to that piano sing. It was my first introduction
>>to a truly great piano. Try this test. The next time you see a Samick, have
>>someone play a 7-8 note chord and hold it down. Now lightly rest your fin-
>>gers on the long side of the case. What do you feel? Nothing, nada, zip.
>>The truth is that junk woods don't sing.
>
>You've listed two possibilities -- I think there are three, which have to do
>with the impedance of the rim. 1) Impedance close to that of the soundboard:
>The case can resonate at musical frequencies, becoming part of the sound
>transducer. This is a more European approach, made for smaller concert halls
>with more reflective walls. 2) The case can absorb and dissipate energy
>quickly (low impedance: imagine a rim made of pillows), which is what you are
>concerned about. 3) The rim can reflect energy back into the board (high
>impedance), which is what Steinway and others with dense maple rims are
>shooting for, in hopes of greater power and sustain.
>
>I don't think a resonant rim is necessarily a sign of a great piano -- just a
>different approach to design for different conditions.
>
>Bob Davis
>
Bob,

I must respectfully demurr.

While the impedence you mention is true for Bosendorfer, it is not the case
for Bechstein, Bluthner, or Grotrian - just to mention a few.

Further, instruments that resonate in all respects, IMO tend to project
better than those that do not.  In this respect, the Bosendorfer is the
clear exception.

Best,

Horace

_________________________________________________________________________
Horace Greeley, RPT                       14 Pyxie Lane
Piano Technician & Consultant             San Carlos, CA 94070-1506
The Colburn School of Performing Arts           415.592.6620
Los Angeles, CA                           horace@compadept.com
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