Seating/false beats

[Richard Moody]

----------
> From: Ron Nossaman <nossaman@southwind.net>
> To: pianotech@byu.edu
> Subject: Re: Seating/false beats
> Date: Monday, April 21, 1997 7:35 PM
>
> At 06:48 PM 4/19/97 -0500, you wrote:
> >
> >
> >----------
> >> From: Ron Nossaman <nossaman@southwind.net>
> >> To: pianotech@byu.edu
> >> Subject: Re: Seating/false beats
> >> Date: Saturday, April 19, 1997 12:40 PM
> >>
> >>
> >> Hi Susan & all,
> >>
> >>
> >> If there were a super lubricant that got you zero friction
between
> >the strings and pins,
> > When struck, the pitch would vary wildly as the
> >string rendered back and forth freely through the pins.
> >
>
>
>
>
>
> >Granted there is no zero friction execpt in the imaginary.  So in
> >reality  does the pitch vary less wildly as the string renders
less
> >freely through the pins according to how much friction is present?

> >
> >R Moody .
> >
> >
>
> Yep. Given a well tuned, stabile piano. I've noticed on some
instruments, a heavy blow will knock a string slightly flat.
Following up with a lot of light to medium blows, the string will
creep back up to pitch! I'm assuming the now overtensioned tail sec.
	Ron Nossaman



Sure a heavy blow can knock a string flat, the same way a heavy blow
can knock a string sharp.    Only because the tensions behind the
friction points were not equal.  That is why it is hard to imagine a
string once knocked flat could be knocked back up to pitch, or even
knocked up at all.  But that is not what Susan's suggestion is about.

So to ask the question directly, explain please?  If there were zero
friction, "When struck, the pitch would vary wildly as the string
rendered back and forth freely through the pins."
 If that is the case, the amount of variance should be be both
detected and measured, and then predicted.  Explanations should also
answer other questions, .ie   Would there be less pitch variance with
a softer blow?  What happens to the pitch when the string looses
energy?  For the pitch to vary wildly, the tension would have to vary
wildly, since its length and mass are not changing. Or does "moving
back and forth freely" mean the length is also varying?

Richard Moody