stability of pitch raises

[Richard Brekne]

Ron Nossaman wrote:

> >Wouldn't adding additional tension to a string cause it to slowly stretch a
> >tad after the initial tension increase? I have always assumed that to be the
> >case when chipping the piano. I know it happened that way on my mother's
> >clothes line (he said, setting himself up).
> >
> >Terry Farrell
>
> There's a pretty big difference between chipping up new strings that
> haven't been under tension since they were drawn and semitone flat strings
> that have been under tension for 75 years. Sure new strings are going to
> stretch. They are also going to have to bend around bearing points and such
> to take the most direct path from hitch to tuning pin, so a lot more string
> will have to be pulled up to increase pitch on new strings, and they will
> "settle" more in the days after the chipping. Not the same animal at all.

I was under the impression that strings rather slowly loose this characteristic,
and to some degree the speed of this was dependant on how often the piano was
tuned, and what kind of climatic conditions the piano had to endure over the
years.... tho granted 75 years should pretty much do the trick.

>
> The plate compression will work the same with either new or old strings.

I was also under the impression that  plate compression also in similar fashion
looses this tendancy...ie as years go by the plate "settles" and becomes more
stable. You want to expound on this one for me a bit ?

>
> Ron N

--
Richard Brekne
RPT, N.P.T.F.
Bergen, Norway
mailto:rbrekne@broadpark.no