action ratios

[Stéphane Collin]

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Re: action ratiosHello Bill

  At first I was thinking of "fly-away" hammers". Then I thought maybe =
that for some reason the the increase in brightness, attack and focus =
might not be linear, but then, that is too numerical.

Well, I applied to all hammer shank centers the usual 5 swing test =
(after hammers were hung, of course).


  But the answer may be buried in your description. May I ask, is there =
an evenness problem in sound in the "out-of-control" mf range? Maybe two =
or three notes per octave are either ahead or behind the entire region =
in terms of the growth of sound, and they are not scattered evenly but =
unexpectedly? Maybe when on listens closely, more than that? It may be a =
voicing problem, and there have been wonderful (if not, brand-name =
based) ideas. But again, is this an evenness problem.

Mmm.  I think the voicing is at least even at all levels.  It is just, =
for every note, that the dynamic response doesn't seem linear.

  Fly away hammers (ie. a low friction action) could be the problem. You =
know, nothing tho hold the hammers back when you pounce on the keyboard. =
Friction is like a parking break, except that it ruins the parking break =
to drive the car around all day with it on. Friction in the piano is =
very necessary for coupling (oh, that word again). Friction should be =
regulated everywhere, but to use it as a reining, harnessing device, the =
best effect is at the hammershank.

Do you mean that in this case I should try to go tighter than the 5 =
swings at the hammer shank ?

  Want a quick reversible check of how the piano would play AND sound at =
a higher level for friction, turn the front rail keypins.

That is a good idea.  I'll try this.  Though, this is not ideal, if I =
did understand that the more controlled effect will happen with more =
friction at the hammer shank centers.

  Oh by the way your test just came back from the lab. See below.





  In addition to a low friction action, you also have very light =
hammers, and I'm willing to bet very little lead in the keys. You've =
calculated the Key ratio.  Did you mention helper springs? This could be =
a very interesting piano. (I know you're trying to push it out the =
door.)


No helper springs on this action.  But this interesting feature typical =
to those pre 1900 Schwander actions : no capstan, but instead a rocker =
system with linked whippen on it.  I already noticed that this feature =
tends to make the action more quick and responsive, if not more =
controllable.  And less friction at that point.

Apart from that dynamic problem, I find this action to be very agreable, =
with ideal touch weight feel (for me) and very quick repetition =
abilities.



  Bill Ballard RPT
  NH Chapter, P.T.G.

  "Talking about music is like dancing about architecture"
      ...........Steve Martin
  +++++++++++++++++++++

Thanks for your thaughts.

St=E9phane Collin.

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