Voicing question

[Ron Nossaman]

Hi Jim,

I think you're exactly right. The swelling panel stiffened the board
assembly and raised the impedance. This should increase the sustain, at a
slight cost to the attack volume, at least in the tenor. I've noticed the
same thing many times. False beats in the killer octave also clear up
somewhat as the bearing angle increases a bit with the higher crown, and the
bridge pins get tighter. The problem with your customer's Yamaha is, the
improvement will be temporary. The soundboard panel, will all too quickly,
compress back down to where it was before the humidity increase. How long
the current improvement lasts will probably depend on how high the "wet"
cycle humidity swings are. The higher the highs, the quicker the
deterioration. If there are enough heater bars in the system to overcome the
high humidity periods, the improved sustain will last longer, but will still
eventually be back to where it was. It's a compression set problem in the
panel, ultimately. That's my call.
 
Ron
  

At 11:00 AM 3/7/98 -0700, you wrote:
>
>Just recently (a week ago) I installed a "wet" humidistat which centers
>humiditiy at 48% RH instead of the usual 42%. My customer who has an
>unusually fine Yamaha CF about 20 years old but rebuilt is always looking
>for more power and carrying power. To our amazement the piano went out 
>of tune but the carrying power increased another major amount. My customer
>had suspected that the tone got better when we had rainy seasons. I think
>I'm convinced now. The customer momentarily is ecstatic.
>
>What do some others of you think who have experienced this kind of change?
>
>My present thinking is that the board has pushed up a little stronger
>against the strings and that the impedance between strings and board has
>changed enough so that there is more resistance of the board to the 
>energy of the string's downward pressure and that this causes the duration
>to increase, but I can't understand the greater power also.
>
>Jim Coleman, Sr.
>


 Ron Nossaman