[CAUT] Erard

[Israel Stein]

At 08:10 AM 5/30/2006, Ed Foote wrote:
><< > My problem is that I cannot find an expert who will give me the
>correct > factory hammer blow distance and factory key depth, as well
>as damper > regulation.<<
>
>     You can find the proper keydip by understanding that the sharps must not
>go farther than approx. 1 mm above the tops of the naturals when depressed,
>and they cannot be above 13 mm above the naturals when at rest. This is your
>range of keydip.  The hammers must not lie on the rest rail, nor be 
>more than 5
>mm above it.  This is your hammer range.  Let-off can be set at 1 mm 
>throughout
>the scale for a beginning specification.  You should then be able to find a
>comfortable set of specs that are tailored to the performers sense 
>of touch by
>varying the amount of aftertouch. ie.

Not on an old Erard, Ed. You better maximize the strike distance if 
you expect to be able to get any kind of a sforzando or forte out of 
that piano. It's a low tension scale - weak attack, long, rich, 
beautiful decay. That's why they designed it with a very long strike 
distance (up to 2 1/8") - you really do need the hammer momentum...

>  if you want to reduce the aftertouch to
>a minumum, (which will be the fastest action), lower your hammers or raise
>your keydip, or a little of both.  You may then want to set your 
>let-off to just
>below the lower excursion limit of the string when the string has been struck
>as firmly as the performer is likely to play it.

Not on an old Erard. Too risky. You need a large safety factor. That 
all-wood action is not so rigid that you can do hair-trigger regulations.

>  The drop should leave the
>hammer at exactly the same height as let-off. Springs should be as strong as
>possible without being felt in the key upon hammer release.

  That's 120 year old springs we are talking about - not much zing 
left... I doubt you'll be able to make the key "kick". Sometimes you 
are lucky to get any kind of lift on the hammer at all - I've had to 
settle for the hammer not dropping back... And if you make them too 
strong (and not even close to "kicking" at the key), the hammers will 
not check. You are dealing with Erard frontchecks (fork in the 
shank/hammer moulding, a ridged metal thingie inside acting as the 
check) which are hell to make work - never mind regulate... 
Especially if someone replaced the hammers and didn't get them 
exactly where they were before...

>The knuckle should be in contact with the top of the jack, but no more than
>that.  The distal edge of the jack should be even with the distal edge of the
>knuckle core.
>      The dampers should begin to lift when the hammer is halfway to the
>string.

Those are under dampers, Ed. They don't lift. And it's really hard to 
tell when the dampers release - they sort of wiggle off the string 
gradually, at a different rate on each damper... And you have to 
regulate them by manipulating a "tongue" on the end of the key - 
which you can only do when the action is out of the piano - so you 
are guessing. Unless you want to start screwing the damper wires in 
and out of the top flange (they screw in - not slip in like on modern 
pianos) - which is a whole different can of worms. Good luck getting 
them to "lift" somewhat near each other - never mind "1/2 stroke".

In short, you can take half the modern action regulation "optimizing" 
assumptions that you are used to, throw them in the toilet and then 
try and figure out how to make the damned thing work.

Israel Stein