<HTML>In a message dated 6/30/0= 3 4:30:01 PM Pacific Daylight Time, RNossaman@cox.net writes: <BLOCKQUOTE TYPE=CITE style="BORDER-LEFT: #0000ff 2px solid; MARGIN-= LEFT: 5px; MARGIN-RIGHT: 0px; PADDING-LEFT: 5px">Likewise, but(t)... Have you ever had the first string you tuned drop suddenly as you were tuning the second or third to it, even after pounding the first string i= nto what should have been adequate submission? Where did the pitch drop come= from? There are only three remotely rational possibilities I can think o= f. One is from the back scale, which I consider most likely in spite of the= pounding. Second is from the coil, which, interestingly enough, will oft= en entertain you with a dramatic pitch drop if you tap on it a bit, but normally won't if you don't. Third is a highly localized structural fail= ure affecting only one string.</BLOCKQUOTE> It's pretty interesting to watch the display on Tunelab as I do a pitch = raise of epic proportions, especially in the killer octave section.   For those unfamiliar Tunelab(Pocket, in my case), it works like this: &n= bsp;each string has it's own spike in the graph.  Get the unison tight,= and there is only one spike.  When I show customers what happens durin= g a pitch raise, and they can SEE the pitch on the neighboring string change= with their eyes(many couldn't be expected to hear it), they begin to unders= tand the concept of a pitch raise a little better. I don't know if it's the backscale or not, but I'm willing to take the w= ord of those with a better grasp of the physics of it. Dave Stahl</HTML>