Yamaha GH-1 Grand

[Brad Smith]

>The solution is a partial rescaling of this section.  Yamaha provides a
>kit for this.
??
I inquired about such a kit from Yamaha a few years ago, and was told that
it did not
exist. At the time, they said I would have to rescale for each individual
GH1, and for that reason, the 'kit' idea would not work.   Does anyone else
know of a kit that is available now?  Perhaps even a set of official Yamaha
instructions on rescaling for this job would suffice.

I would also be wary of promising a customer that 'voicing' or 'regulation'
can solve this, although it does help disguise it somewhat.   It still
baffles me why this can't be, or isn't, changed in the
designing/manufacturing.  I heard a top technician for Yamaha say that the
GH1 was originally conceived as a counter to the Kimball LaPetit.  He said
if they changed this, it would begin to resemble a C1, and if that's what
the customer wants, they should buy a C1.  I am reluctant to tell a customer
this right after they have spent several thousand dollars.   And, Gina's
experience shows that even before the purchase, they don't always listen
anyway.   I have several GH1 customers, and most are happy with their
pianos.  But, I do have to be clear with them as to what I can and can't
change with this model, in the course of one tuning. As always, it comes
down to choices, and communication.

Brad Smith, RPT
Manchester, NH

From: Billbrpt <Billbrpt@aol.com>
To: pianotech@ptg.org <pianotech@ptg.org>
Date: Saturday, February 28, 1998 11:40 PM
Subject: Re: Yamaha GH-1 Grand


>In a message dated 98-02-28 23:31:57 EST, you write:
>
><< Does this model have a problem in the stringing scale?  Shoud I re-scale
>it, or does Yamaha have a new scale for it?  I do not want to my client to
>waste $$$ on rescaling and restringing it if it will not help.
> I am not sure it is voicing or if my ears are going whaky.  Your advice
will
>be much appreciated. >>
>
>   Yes, there is a problem with the low tenor.  You can tune it but it will
>always be unstable and the "shallow" sound you are hearing is normal for
this
>piano.  The numerical values that result in good octaves,  3rds, 4ths, &
5ths
>will not be those provided by an FAC or similar program.
>
>     The inharmonicity of these notes is way off from where it normally
would
>be. The tension on the lowest six unisons is very low.  Imagine any other
>piano with a normal and good sound somewhere in the midrange and taking six
>notes in a row and lowering their pitch by two whole steps or more.  You'd
>have that same sound you are encountering with the Yamaha GH-1 in the low
>tenor.  You could still tune those notes either by ear or with the SAT but
>they wouldn't sound right to you, voicing would not help much and their
pitch
>would be very unstable with the slightest change of humidity.
>
>    The solution is a partial rescaling of this section.  Yamaha provides a
>kit for this.  All you have to do is change six agraffes, six dampers,
drive a
>few new holes for some hitch pins and replace the plain wire unisons with
>wound string bichords.  The middle tuning pins with no string attatched are
>simply left at the same level as the others for appearence sake.  You can
do
>it in a few hours.
>
>    This is not the only piano which has this problem.  You may find a
similar
>problem with any small grand or verticle with notes anywhere below D#3 in
the
>tenor that have plain wire.   If you do not have the ability or want to for
>any other reason not to go to the trouble of designing wound strings for
this
>section, you can use heavier wire than the original up to a point, then you
>can convert to very heavy plain wire bichords.  You will find some pianos
>already scaled that way.  While the wound string conversion is the best
>solution, any solution will always be somewhat of a compromise.
>
>   The heavy plain wire trichords and bichords will have a very powerful,
>"boingy" sound to them but you can voice the hammers to compensate.  Too
much
>power and higher inharmonicity will always be the result of using heavier
wire
>in this section.  If you ask me however, I would rather deal with a loud
>brassy tone than a weak, "shallow" tone, as you describe it, which is the
>result of wire which is at such a low tension than it is loose and flabby.
>
>    James H. Donelson RPT's PIANO REBUILDERS' HANDBOOK OF TREBLE STRING
>TENSIONS, which may still be available from the supply houses, can help you
>analyse the problem and find the right wire.  If you look up the tension
>values for this section of the Yamaha GH1, you'll find the figures to be
>extremely low.
>
>    If you decide to use very heavy wire bichords, the wire size you choose
>may even be so heavy that it is off the list.  You have to remember that if
>you make this decision, you are dropping one of the strings and therefore
some
>of the load.  It would not be out of line therefore to use some of the
>heaviest wire available, 22-25 in the lowest bichords.  Donelson's book did
>not really cover the idea of plain wire bichords.  Plain wire trichords
with
>very heavy wire would usually not be considered and therefore his list
stops
>short of providing the data for the heaviest wire for these string legnths.
>
>    Bill Bremmer RPT
>    Madison, Wisconsin
>