Tune it where it is

[Newton Hunt]

Hi Terry,

Two things can happen.

If a bass string is over pulled the windings can be separated too much
and the twist in the string can take a "set" (effectively unwinding
the twist (no proof of this)) or the winding can come loose at the
ends deadening the string.  Another fact, for a string to sound best
the wraps fo the copper have to have room between sufficient to allow
them to pass each other, not rub when vibrating.  Also if it is a high
tension string like on a Baldwin or Steinway they can break.  The
strongest link is the weakest chain.

In the high treble wire sustain of the string itself (no the board,
different issues entirely) is dependent upon its ability to stretch
and unstretch for each half cycle.  A 4,000 Hz string would be doing
this 8,000 times per second.  If a string is stretch beyond it's
elastic limit then it cannot do this as easily or well so some sustain
is lost and eventually it will break before it's neighbors, all things
being equal.  That is why knowing breaking % of the wire size relative
to it's size is a bit important.  

Something I learned from Steve Fairchild, any wire size will break at
the same pitch.  A 14 wire will break at the same bitch a 18 wire will
_with the same speaking length_.  This is why speaking lengths are
important in designing a scale.

Fun things to know no?

		Newton



Farrell wrote:
> 
> ----- Original Message -----
> From: Newton Hunt <nhunt@jagat.com>
> To: <pianotech@ptg.org>
> Sent: Tuesday, January 11, 2000 11:21 AM
> Subject: Re: Tune it where it is
> 
> > .......It is safe to raise the pitch of a newish piano by 40 cents.  Much
> > more than that you risk over stressing the strings and shorten their
> > sustain time. .....
> 
> I was not aware that overpulling a string during a pitch raise could affect
> the sound production characteristics of a string.... any more on this?
> 
> Terry Farrell
> Tampa, Florida