Mutiple bouncing

[Dave Nereson]

----- Original Message ----- 
From: "Jere Fryett" <jfryett@minot.ndak.net>
To: <pianotech@ptg.org>
Sent: Wednesday, May 26, 2004 7:56 PM
Subject: Mutiple bouncing


> Dear List,
>
> Several of the new Yamaha P22's and M600's that have been coming into the
> store here in Minot have terrible multiple bounce problems on very soft
> playing.  I have tried several things and nothing seems to work for
> me.  The specs seem to be on or at least fairly close.  For key height I
> get 58mm from the key bed but only 19mm from the top of the key slip to
the
> top of the key.  The hammer strikes the wire before the jack is halfway
> out.  Loud playing or even moderately loud playing gives no problem, it is
> just that very soft, light touch that gives the problem.
>
> What should I do short of a full regulation?  Is there a quick fix?  I
have
> some luck increasing the key dip but not a lot.  There are people looking
> at these pianos but they bounce so badly they are getting turned off.
>
> Thanks for your help.
>
> Jere

    I worked for a Yamaha dealer for 7 years and Yamahas, especially
consoles, have had the double-striking problem for a long time.  It's partly
due to the Schwander-type butt spring rather than the old type (not as
strong), sometimes the hammer-butt pinning (but I forget if too tight or too
loose makes it double-strike -- probably too loose), and, apparently, the
damper spoon regulation (I hadn't heard that one before).  Yamaha admits to
this and usually advises to make sure there's no lost motion and that key
height is not low and dip is not too shallow.  They also used to tell you to
tell the owners/players to make sure they're striking the keys with blows
that don't hesitate in the middle of the stroke, in other words, make sure
they're not "trying to get it to double-strike"  (I'm sure most of them are
not).  You can try bending the butt spring a little stronger (take it out of
its loop, bend up, put back).  If the blow is a bit wide, you can shorten it
a bit and take out the resulting lost motion.
    Sometimes everything's a little tight when new, on purpose, since they
know it will wear in and loosen up with playing.  But if its hurting sales,
you should call Yamaha and tell them that and ask what to do.  Ask about the
butt flange pinning and whether too tight or too loose helps cause
"bobbling."
    I've encountered many Kawai consoles with the same type butt spring that
have the same problem.  I know that's not the only culprit, but . . . (?)
    Make sure the jacks are coming away from the butt leather and not being
hindered by the regulating rail (let-off rail).
    --David Nereson, RPT and Little Red Schoolhouse alum