<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <HTML><HEAD> <META http-equiv=Content-Type content="text/html; = charset=iso-8859-1"> <META content="MSHTML 6.00.2800.1400" name=GENERATOR> <STYLE></STYLE> </HEAD> <BODY style="FONT-SIZE: 10pt; FONT-FAMILY: Arial; BACKGROUND-COLOR: = #ffffff" bgColor=#ffffff> <DIV>Wm:</DIV> <DIV>I too have experienced slipping unisons which seem difficult to = explain. I've thought about it for years. I have a theory which I call = "SOUNDBOARD SHAKING" for lack of a better term.</DIV> <DIV> </DIV> <DIV>We strike the keys hard during tuning to settle the segments of the = string. Maybe there are still tidbets of friction left as the string snakes = through the bridge pins. Just striking each individual string isn't enough to = free the friction. Later during hard playing the soundboard and bridges are = SHAKING more intensely and these bits of friction surrender and the unison goes out = of tune. Maybe there is more friction in the bridge pins than the agraffes, upper = bearing and capo bar. </DIV> <DIV> </DIV> <DIV>It's just a theory. How can one prove it?</DIV> <DIV> </DIV> <DIV>Sy Zabrocki</DIV> <BLOCKQUOTE dir=ltr style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; = BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px"> <DIV style="FONT: 10pt arial">----- Original Message ----- </DIV> <DIV style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: = black"><B>From:</B> <A title=Wimblees@aol.com = href="mailto:Wimblees@aol.com">Wimblees@aol.com</A> </DIV> <DIV style="FONT: 10pt arial"><B>To:</B> <A title=caut@ptg.org href="mailto:caut@ptg.org">caut@ptg.org</A> </DIV> <DIV style="FONT: 10pt arial"><B>Sent:</B> Saturday, April 10, 2004 = 12:22 PM</DIV> <DIV style="FONT: 10pt arial"><B>Subject:</B> why does a string go = out of tune?</DIV> <DIV><BR></DIV> <DIV>OK, what exactly is happening when a string goes out of tune. I = know about climatic changes that effect the soundboard. This causes the who = piano, or at least whole sections to go out of tune. I can accept that. But I = pride myself on setting the string and the pin. I am a pounder. On new = pianos, (at least new to me), and especially concert instruments. I beat the = daylights out the notes to get them to stabilize. But there are still strings that = go out. That is why we tune concert instruments numerous times, with strings = still going out. </DIV> <DIV> </DIV> <DIV>I tune a D for a church once a month. I pound until my fingers = hurt but I leave the string with the lights standing absolutely still. But = every time I tune it, the piano is "in tune" in that it hasn't changed pitch = over all, but there are at least 2 dozen strings that have "slipped." They = are 2 or 3 cents off. I'm not talking notes, I am talking string. The right = string of one note is 3 cents low, or the left string of another note is 2 cents = flat. </DIV> <DIV> </DIV> <DIV>Why is that? Why do just these strings go out, and not the other = ones? Am I still not pounding hard enough, or is the combination of slight = variations in temperature, combined with strings that maybe weren't set right, = causing this? Inquiring minds want to know.</DIV> <DIV> </DIV> <DIV>Wim</DIV> <DIV><FONT lang=0 face=Arial size=2 PTSIZE="10" = FAMILY="SANSSERIF">Willem Blees, RPT<BR>Piano Technician<BR>School of Music<BR>University of Alabama</FONT></DIV></BLOCKQUOTE></BODY></HTML>