Yamaha GH1B

[Ron Berry]

> To:            pianotech@ptg.org
> Date:          Tue, 26 Aug 1997 18:10:52 -0500
> Subject:       Yamaha GH1B
> From:          wjstuner@juno.com (William J Schlipf)
> Reply-to:      pianotech@ptg.org

> Dear List:   Am having difficulties with a new GH1B in the low tenor.  B3
> (2 B's below middle C) has the least desireable sound ever heard.  It's
> not out-of-tune,  strings are level,  hammer is striking squarely, no
> kink in the wire,  not beating false.  What am I forgetting?  Tone is
> thin and harsh.   Any suggestions would be be greatly appreciated.  
> Thanks in advance!!   Bill    WJSTuner@juno.com
> 
> 
Bill,

This is not a voicing problem.  The problem is the scaling of the 
strings in the low tenor.  Every piano has this problem to some 
degree but the GH1 is one of the worst I have seen.  It's the same 
problem that keeps you from tuning the G below middle C on an 
Acrosonic.  The strings in this area are too short.  This means that 
they have to put thicker wire but then the inharmonicity goes up.  So 
you have tenor with very low tension about 30% of the breaking point 
and high inharmonicity next to bass strings with low inharmonicity 
and 65% of the breaking point.  This is the reason the tenor goes out 
of tune so radically with weather changes.  Later models put a couple 
of wound unisions on the tenor side of the break.  This is the only 
answer, but the whole low tenor is bad enough that it doesn't make a 
huge differnce.  

You can help a little with voicing but  don't overdo it or you will 
kill off the fundamental and just have those strange harmonics left.  
Sometimes pushing a needle through the side of the hammer under the 
strike point will help.  This is one of those cases where you have to 
know that you are beat before you start and that you can never get a 
nice smooth tone across the break.  Yamaha is a great company and 
make many wonderful pianos but the GH1 just doesn't live up to the 
rest of their models.  Some of the other small grands are humidity 
sensitive at the break but none of the other have the tonal problems 
of this model.

Ron

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Ron Berry, RPT, Indianapolis, IN
mailto:ronberry@iquest.net
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