Agraffe tuning easier or not?

[Farrell]

> It is easily possible to design a string termination system that keeps the
> energy in the speaking portion of the string until it is transferred into
> the soundboard system. For examples look at the typical upright design.
> Simple and effective. Keeps the string angles reasonable and short. No
noise
> and no tricky work required on the V-bar except with the most sloppy plate
> castings. Geometry wise this is a bit tricky to pull off on a grand plate,
> but there are other ways of accomplishing the same thing.

So maybe my little 1906 Everett with the cast V-bars and pressure bars -
just like an upright - has some potential? Have you run across one of these
before?

Terry Farrell

----- Original Message -----
From: "Delwin D Fandrich" <pianobuilders@olynet.com>
To: <pianotech@ptg.org>
Sent: Tuesday, June 26, 2001 10:16 PM
Subject: Re: Agraffe tuning easier or not?


>
> ----- Original Message -----
> From: "phillip l ford" <fordpiano@lycos.com>
> To: <pianotech@ptg.org>
> Sent: June 26, 2001 5:46 PM
> Subject: Re: Agraffe tuning easier or not?
>
>
> > ------------------
> > Why do you say that the Sohmer and Heintzman designs are taken to an
> illogical extreme?  I haven't heard a broad sampling of these pianos but
of
> the ones that I have heard I thought the top ends were pretty nice.  I
> attributed that partly to the connected capo.
> > ------------------
>
> Both were very difficult plates to cast and machine. Any improvement in
> actual performance due to this feature is so small as to be virtually, if
> not in fact, undetectable. While it is possible to measure some movement
of
> the capo d'astro bar in response to both the hammer impact against the
> string and to the vibrating string, it is doubtful that the loss of
audible
> energy to this alone is either detectable by ear or measurable by machine.
>
> I have heard some Sohmer and Heintzman grands with this feature that had
> quite nice treble sections and some that had quite poor treble sections.
I'd
> look elsewhere for the reasons.
>
> If you'd like to couple the capo d'astro bar to the pinblock panel, the
> Baldwin system of individual termination pieces with a machine screw going
> to either is a better solution. Even though the part itself is rather
costly
> it is probably still easier and more economical than either the Sohmer or
> the Heintzman system.
>
>
>
> > ------------------
> > It seems that there is going to be some inevitable 'leakage' past the
capo
> bar or agraffe.  So the string portion on the side of the capo opposite
the
> speaking length is going to be moving.  You say that energy is being lost
by
> having a tuned aliquot design. Do you feel that less energy would be lost
by
> having a detuned aliquot design or by having this section damped out
(felted
> out) altogether?
> > -------------------
>
> No. You don't want it to get there at all. Once the energy is there,
damping
> it out just makes a bad situation worse.
>
> It is easily possible to design a string termination system that keeps the
> energy in the speaking portion of the string until it is transferred into
> the soundboard system. For examples look at the typical upright design.
> Simple and effective. Keeps the string angles reasonable and short. No
noise
> and no tricky work required on the V-bar except with the most sloppy plate
> castings. Geometry wise this is a bit tricky to pull off on a grand plate,
> but there are other ways of accomplishing the same thing.
>
>
>
> > -------------------
> > Why is the Baldwin design inherently inefficient?
> > -------------------
>
> The string angles are too shallow and the duplex length is too long. (OK,
> those with the back-bearing riser reversed are better.) Otherwise it's a
> great system.
>
> -- Del
>