[CAUT] Wire Stretch

[John Delacour]

At 12:08 pm -0500 29/4/07, Ron Nossaman wrote:

>But then no one that I'm aware of has ever reported a pitch rise in 
>the speaking length from seating a string. They all report a pitch 
>drop, often of nearly a quarter semitone. If there is significant 
>tension difference between string segments, the rear segments will 
>be of higher tension than the front segments at least part of the 
>time.

I would say exceptionally, a very very small part of the time.  Even 
if at the factory the utmost pains are taken to equalize the tension 
throughout the length of the string before its final tuning at the 
gate, unless all subsequent tuners pay attention to equalizing the 
tension, which would be an extraordinary occurrence, the tension in 
the speaking length is always going to exceed the tension between the 
bridge and the plate, and the excess will grow with time.  The shock 
of "seating the strings" does overcome the friction at the bridge and 
send a proportion of the excess tension across to the back-length, 
hence the drop in pitch. I presume the familiar high-pitched "click" 
or "squeal" is a longitudinal vibration of very short duration as the 
wire scrapes past the pins.

JD