Fw: D hammers - is action stiffness , inertia/friction ratio ? -comfort

[Isaac OLEG]

Hello Rich

The accelerometer can possibly provide an answer to the bridge move
question I guess.

I've seen some setup at the IRCAM, but it was really not easy to be
accurate enough, because of the quality of the (old Petrof grand)
piano.

Greetings

Isaac OLEG

Entretien et reparation de pianos.

PianoTech
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FRANCE
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> -----Message d'origine-----
> De : Richard Brekne [mailto:Richard.Brekne@grieg.uib.no]
> Envoye : dimanche 27 avril 2003 12:41
> A : oleg-i@wanadoo.fr; Pianotech
> Objet : Re: Fw: D hammers - is action stiffness ,
> inertia/friction ratio
> ? -comfort
>
>
>
>
> Isaac OLEG wrote:
>
> >
> > It is certainly possible with very fast cameras and analysis, to
> > determine what happen at different level of velocities,
> and I suspect
> > that there are different response mode within the top
> action, I don't
> > believe at the oversimplification that say that the
> pianist is only
> > allowed to control the velocity of the hammer. The
> contact moment is
> > shortened or lengthened depending of the attack angle
> when the hammer
> > hit the string, most probably. The moment of inertia of
> the shank is
> > allowing for some distortion is not it ?
>
> While you and I tend to agree more then we disagree here
> Issac, I suggest
> you read (if you have not already done so) relevant publications by
> Alexander Galembo. Also Anders Askenfelt has published some
> interesting
> stuff along these lines.
>
> As I said a couple days ago.  Most of this, while not claiming any
> conclusive truths... point in the direction that Bill
> Ballard and others
> believe. though I think its important to underline that
> these Ph'D's dont
> claim << conclusive proof >> for good reason. And
> Alexander's work points
> off in another direction entirely me thinks... one that isolated
> accelerometer experimentation cant really address.
>
> Cheers
>
> RicB
>
>
> --
> Richard Brekne
> RPT, N.P.T.F.
> UiB, Bergen, Norway
> mailto:rbrekne@broadpark.no
> http://home.broadpark.no/~rbrekne/ricmain.html
>
>
>