Touch Weight

[Isaac sur Noos]

Ric, yes I mean the first statement, more lead in the key makes the
beginning of the stroke "fuzzy, or sluggish" , then with acceleration,
the key is having less control (it moves on it's own preferred
velocity) I feel that like assisted turning in cars, comfortable, but
less direct.

I just find that this induce a supplementary sensation that rob some
tactile feedback, being felt as a "filter" between the pianist's hand
and the hammer.

Indeed not physician terms, but if I want to use them, I'd say that
the higher mass of the key slows it at the beginning of its move,
afterthat it shows a lower moment of inertia than with (lets say) the
same FW and leads located nearer the key front. Immediatness of the
action response is a little delayed.

May be we should look at it like if the moment of inertia of the
global action, not only the key, may not be too low, the pianists
finger may be able to press on the key for a decent amount of time
with a more or less linear sensation under it... (then accelerate the
motion, or use the kinetic energy given so the stroke finish on
itself).

That is what professional pianists call "using the key inertia to play
faster" (moment of inertia seem to be the good term)

Talking about the key landing on the punching, having more lead near
the balance adbsorb part of the energy "stored " in the key (flex), I
believe, and the action is less powerful then. The thump of the key is
synonym of release of the key flex, that is the ultimate stade of
hammer propulsion in high FFF velocity modes I suppose.
it is an old standard trick in France on antic less powerful pianos to
use 2 non-cloth felt punching to obtain a very firm (and noisy)
landing that give also a little supplement of attack power (and the
impression of puissance to the customer).


I've tested and regulated an action with a very even BW on an
otherwhile uneven accelerated action (the sharps for instance asking
for more dip than the whites because of the move of the capstan) WHile
there was a very perceptible sensation of eveness in slower playing
modes, this sensation is not there in dynamic mode, when the pianist
try to use different accelerations to have different tones or attacks.

Then indeed this action had somehow heavy hammers (mean low top I
guess) assist springs, 115mm spread, and a very large move of the
capstan on the sharps (that where acting almost on the edge of the
whippen cloth )

All those parameters induced a lot of action fatigue, repetition
springs have to be way too much stiffened, the underside of the sharps
have been filed in an arch just in the middle of the balance hole to
gain cleareance (or to change the leverage of the sharps) - then the
hole is pulleying to death.

It is interersting to notice that because of the lightening of the
whippen produced by assist springs, the sensation of eveness of the
front weight was so perceptible, that allows me (and the pianist) to
discover that this eveness in particular was of no use for musicality
because it is there mostly in ligher modes of playing (while I don't
mean it should not be considered, but it is just a comfort parameter
among others)

I noticed also that modern keys are often not very good, and adding
mass to them tend to accelerate wear at the balance hole and the
bushing.

That is why I say the comment from Mr Ellis is valuable, some
practical normal way to do the usual things have always some value in
it (like avoiding vinyl glue for bushing clothes !)

On motion pictures we can see the keys flexing a lot like if it was in
rubber, drilling a lot of holes in them is very dangerous in my
opinion.

Well... jumping from one idea to the other, we are just out of the
initial subject certainly.

Best Regards And have nice times .

Isaac

------------------------------------
Isaac OLEG
accordeur - reparateur - concert
oleg-i@noos.fr
19 rue Jules Ferry
94400 VITRY sur SEINE
tel: 033 01 47 18 06 98
fax: 33 01 47 18 06 90
mobile: 033 06 60 42 58 77
------------------------------------


> -----Message d'origine-----
> De : Richard Brekne [mailto:Richard.Brekne@grieg.uib.no]
> Envoye : samedi 20 decembre 2003 23:31
> A : oleg-i@noos.fr; College and University Technicians
> Objet : Re: Touch Weight
>
>
>  Isaac... I would echo others sentiments about the good
> form of deleting
> unneccessary text from previous posts.
>
> A comment below on one of your points.
>
> Isaac sur Noos wrote:
>
> > Ed,
> >
> > My experience on heavily loaded keys is that they have a
> less large
> > range of acceleration available.
> > That seem to concur with what Don is saying us actually.
>
> I think you need to clarify exactly what you mean here.
>
> If you mean keys with identical FW yet difference of mass levels and
> placement... then you are going to get some argument. If you mean
> essentially higher FW levels.. then no one is going to argue.
>
> But if you do mean the former... I dont think thats what
> Don is saying.
>
>
> Cheers
> RicB
>
> --
> Richard Brekne
> RPT, N.P.T.F.
> UiB, Bergen, Norway
> mailto:rbrekne@broadpark.no
> http://home.broadpark.no/~rbrekne/ricmain.html
> http://www.hf.uib.no/grieg/personer/cv_RB.html
>
>
>