Down on the Hitch Pin Web

[Jim Coleman, Sr.]

Hi Bill:

My take on your situation is that you would have to crank down quite a bit
more to see any change on your dial indicator as far as downbearing is
concerned. The soundboard is more flexible than the plate, so it goes along
with minor changes in the plate. If you were to reach the place where the
board is so constrained that it can not move anymore, then you would begin
to see some DB indication. Conversely, if you were to lower just one string
on a Baldwin AccuJust hitchpin, you would not notice any change in the
neighboring note's DB, but there would be a tremendous DB change in the one
you lowered. However, the tone of that one note would not be affected 
measureably. If you then lowered the rest of the notes in that area, you
would notice a tonal change, but the DB of the original note would not be
as much as when you first set it.

Most of the better pianos which I have measured show a consistent DB of
.010" or around 1 1/2 degrees.

Jim Coleman, Sr.

On Wed, 24 Jun 1998, Bill Ballard wrote:

> Esteemed Colleagues, I'd like to know what's real here, so pitch in
> 
> A 1901 Stwy B (with a new belly at the factory restoration center in 1941)
> sits in the carvernous dining hall of a local private school and is tried
> (and selected for use) by pianists involved in a summer chamber music
> program for college-agers just down the road. This piano has very
> respectable resonance judging by the direct sound (not being fooled by the
> ambient reverberation of the dining hall).
> 
> The piano gets moved to the summer music program's main performance stage,
> a small, nicely remodled barn (we're talking rural VT here, gang), and
> immediately the musicians complain that the top third of the piano is dead.
> My first reflex, to file hammers, sharpens up the sound, but the impression
> of poor balance of that region with the rest of the scale remains for the
> pianisit, violinist and cellist preparing for the season opener. We explore
> many ideas. Given the tropical RH here ever since the end of May and the
> unaimous description "it sounds stuffed up", we choose to run the powerful
> air conditioning full time (and set about 200W worth of desk lamps on the
> floor under the board) on the assumption that high RH increases crown
> increases downbearing increases board loading which decreases sustain. (The
> standard dial indicator reads 10-15 mils of db in that region, and db
> throughout is ample.) Maybe the hammers are water-logged,though they're all
> ready filed down to the nub.
> 
> Yes, although both spaces are remodeled barns, the smaller space has no
> reverberance. (For years it has relied on direct sound, and the  consensus
> this morning is that the strings have no trouble projecting.)
> 
> The pianist then mentions a technician once worked a miracle with a similar
> dead treble by adjusting the bolt which ties to the bell. (He has no idea
> in which direction.) I crank crank up 3/4 of a turn until the bolt is
> loose. The pianist plays, but nobody hears any difference. I go back down
> to the starting point, and beyond by 1/2 turn until it begins to require
> uncomfortable amounts of torque. In neither case does the dial indicator
> show a change in db. But going down, they all say, yeah that sounds more
> like it.
> 
> What's going on here? Is there a real effect? There is of course Rick
> Davenport's oft-told story of Heiner Seinwald doing exactly this same thing
> (or recommending that Rick do the same). I can understand not seeing an
> immediate change in db on the way upwards, as  the plate might not
> immdiately react to take new upward freedom. But what gives in the
> direction down when the db doesn't show a change and the musicians hear a
> difference? Is the pianist simply getting used to the newly filed hammers?
> 
> I less interested in suggestion on voicing (or for that matter, new
> strings/hammers which it badly needs, or even discreet sound reinforcing)
> than on people's specific experience with reseting the htich pin web at the
> bell.
> But I'll consider all comments (including the one about the santero priest).
> 
> TIA
> 
> Bill Ballard, RPT
> New Hampshire Chapter, PTG
> 
> "May you work on interesting pianos."
> Ancient Chinese Proverb
> 
> 
>