bass to treble break problem

[PIANOBIZ@aol.com]

In a message dated 96-06-14 18:45:24 EDT, Ted Simmons writes:
>I'm fairly new on this listserver and maybe this has been covered before.
>I was wondering if anyone has come up with a solution to correct the
>situation where the first treble string above the bass-to-treble break in
>an upright kind of thunks. Without raising the cover of an upright, I can
tell
>where the bass-to-treble break is just by playing the notes.  I've called
> manufacturers and they said that nothing can be done.
>Has anyone attacked this problem and come up with a solution?

Ted
This problem has been addressed by my father, Al Sanderson probably for
fifteen years.  Based on his formulas we can redesign this section of the
piano, converting the plain wire trichords on that lower tenor bridge to
finely wound bass string bichords--with excellent results.  It is now
possible to accomplish a very smooth and truly indiscernable transition
through that section using this method. This kind of work is usually done in
conjunction with a rebuild as it involves rescaling the entire piano and some
re-manufacturing of this section. (Replacing three-holed agraffes with
two-holed, converting the damper felt to wedges, cosmetically filling in
extra tuning pin holes in the plate, adding a hitch pin or two at the other
end)

Les Smith gave you some practical things to check in his previous post, any
of which could cause the symptoms which you described.  If none of those are
causing the problem, then rescaling and remanufacturing is your only cure,
but it is an involved cure.

Happily, manufacturers are now waking up and correcting the weaknesses of the
past. This is encouraging.  Before ceasing piano production, Kimball had done
extensive redesigning of their scales using my father's formulas.  In one
model they actually relocated the lowest part of the tenor bridge to improve
the transition area.  They cut off the original tenor bridge, four notes from
the bottom and glued that piece onto the board in a different place,
completely separate, and wound some bass string bichords for this little
floating bridge. It sounded beautiful.  It looked funny...you could see how
they had done it because that bridge section still had the three bridge
pins/note in it as per the original design. They just left the middle pins
blank.  Alas it hit the market too late to aid in their recovery.

It has been my observation that the rescaling and remanufacturing process has
been much more effective on the grand piano than the old upright.  I'm not
sure why, perhaps this is related to the enclosed cabinetry of the old
upright. Weak soundboard? Has anyone else noted this? The grands always seem
to respond so much better than the old uprights.

David Sanderson
Sanderson Accu-Strings
410 Great Road, Suite A-4
Littleton, MA 01460
Pianobiz@aol.com