double striking hammers

[Yardbird47@aol.com]

Vince Mrykalo rote, 10/2:

<<We have a C-7 (Yamaha) that double strikes on certain pianissimo
playing. The latest thing I tried was to increase let-off to 1/8th of an
inch.  I am thinking that the jack top can be bevelled on the "hammer" side
to maybe fix it.>>

You're on the right track. It's the nervous tick in well-regulated actions.
That is, closely regulated. What happens is that even after strike, the jack
has still not pulled out from under and away from the knuckle, and is
bouncing in between the top of that jack and the string (if you can picture
that). This sort of thing occurs when you push the regulation real close.
(I've always looked at regulation settings as going from inffective to
dangerous.)
Here what is likely happening is that to maximize repetition, the action has
been given strong rep springs, and high LO and drop. Your pianist sits down
and whenever the pressure driving the parts is enough to get the hammer to
the string (especialy with the afore-mentioned close LO) but yet not strong
enough to push through the escapement (whose "weight" has been aded to by
extra rep spring pull on the jack), it will bubble. For me, it's the action's
way of telling me, "Back Off!" (Pun intended.)

Of course this is two days later and you've probably had six other people
tell you that.

Bill Ballard RPT      "Never try to teach a pig to sing. It wastes time
NH Chapter, PTG        and  annoys the pig."  Sign on the wall of a
                                    college voice teacher's studio.

(Do I have any snappy on-liners about Da Jooce? Not. Nicole's life was no
joke......