Flatstrung vs straightstrung

[John Delacour]

At 2:31 PM -0500 12/2/01, Farrell wrote:
>Hmmm. Then the source of my confusion was your reference to "bridges
>converging on the center of the soundboard". Don't most flatstrung (not
>overstrung) pianos have only one very long bridge? Or is there a separate
>bass bridge? If so, the upper end of the bass bridge is presumably very near
>the lower end of the tenor area of the long bridge?

Terry, in the very old days they did have only one bridge, like the 
harpsichord from which they were taking over.  The hammer action was 
taking over but an initially very similar acoustic structure 
gradually evolved as the piano slowly gained acceptance during 18th 
century and early C19.  John Broadwood (d. 1812) was the first to use 
the bass bridge.  I thought I had a reference to a patent, but I 
can't find it.  Pianos at the time would be 5 rising to 6 octaves and 
Broadwood was of course the world's leading maker at that time and 
for some while afterwards.  Stephen will probably know exactly when 
the bass bridge was brought in.**

There is a considerable gap between the long bridge and the bass 
bridge (say 4" -- I'm not in measuring or visualizing mood) since the 
whole point of the thing was to improve the scale by shortening the 
strings at the critical point where they were getting unmanageable.

JD



** Ah I've found it...it would be about 1785...

"Dr. [Edward Whitaker ] Gray [of the British Museum, advisor to John 
Broadwood] demonstrated that if the string could be struck at about 
one ninth of the vibrating length of the string, this would produce a 
better tone.  To achieve this, John Broadwood divided the bridge, 
introducing a separate bass bridge.  The innovation was immediately 
successful and within a short time was adopted by all piano makers" 
-- Wainwright