No downbearing ? REVISITED

[John Hartman]

David Skolnik wrote:

> John's response is, I think, unintentionally misleading. He first 
> suggests that Jean-Jacques's  statement is correct, but then immediately 
> attributes to downbearing the [important?]ability of controlling "the 
> rate at which the vibrations move from the strings into soundboard". If 
> there is a point of differentiation to be made here, it seems 
> inordinately subtle, compared to the resulting impression conveyed that 
> downbearing is not an essential component in piano design and 
> engineering. Unless that is the meaning that is intended!?

David,

If a piano has no down bearing the vibrations of the strings will still 
find their way into the soundboard. People often have the wrong notion 
that down bearing helps to get the vibrations into the soundboard by the 
simple act of pressing the string down on the bridge, as if that force 
would help to make a better connection - like some sort of electrical 
connection. I was pointing out that down bearing is an indirect effect. 
Down bearing is one of many factors that control the rate at which the 
vibrations in the string will flow into the soundboard. It does this by 
altering the impedance of the soundboard in relation to the vibrating 
string. It is not a note by note or a string by strings effect. If many 
strings bear down on the soundboard the apparent stiffness of the 
soundboard and bridges will increase. Then a vibrating string will lose 
energy through the bridge into the soundboard at a somewhat slower rate. 
  More of the energy will bounce off the bridge back into the string.

So I stand by my statement that down bearing is not necessary in order 
have the vibrations in the string transfer into the soundboard. And 
Jean-Jacques is right in saying that "the mere "grip" that the string 
has on the bridge being sufficient to assure this transfer." That grip 
provided by the side bearing of the strings through the staggered bridge 
pins.

John Hartman RPT

John Hartman Pianos
[link redacted at request of site owner - Jul 25, 2015]
Rebuilding Steinway and Mason & Hamlin
Grand Pianos Since 1979

Piano Technicians Journal
Journal Illustrator/Contributing Editor
[link redacted at request of site owner - Jul 25, 2015]