<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <HTML><HEAD><TITLE>HTML Message</TITLE> <META http-equiv=Content-Type content="text/html; = charset=iso-8859-1"> <STYLE>P { MARGIN: 0px } </STYLE> <META content="MSHTML 6.00.2900.2722" name=GENERATOR></HEAD> <BODY style="BORDER-TOP-STYLE: none; BORDER-RIGHT-STYLE: none; = BORDER-LEFT-STYLE: none; BORDER-BOTTOM-STYLE: none" bgColor=#ffffff> <DIV><FONT face=Arial size=2>I may have found another use for pitchlock.</FONT></DIV> <DIV><FONT face=Arial size=2></FONT> </DIV> <DIV><FONT face=Arial size=2>I have a 1923 Sohmer 5'4" cupid = grand.  I rescaled it using pscale.</FONT></DIV> <DIV><FONT face=Arial size=2></FONT> </DIV> <DIV><FONT face=Arial size=2>The sound of  A2 note 25 was what = I'll call nasty.  I've heard this sound many times</FONT></DIV> <DIV><FONT face=Arial size=2>and have never managed to fix it.  = I had no clue what caused it.  Voicing had no effect.  Basically it = sounds like a fairly high pitch twang (partial) that appears abruptly when starting = at very low and gradually increasing the volume.  A tuner friend checked = the piano and when I pointed out what I thought was a nasty note, he said "Yes, I = hear what you mean but if you hadn't said anything I wouldn't have noticed = it".  Another said "There are other notes that sound worse".  I = think he was talking about a different kind of worse.</FONT></DIV> <DIV> </DIV> <DIV><FONT face=Arial size=2>I finally thought maybe it was a = longitudinal problem and I don't know what that even sounds like.</FONT></DIV> <DIV> </DIV> <DIV><FONT face=Arial size=2>The pitchlock clips I had were too = small so I fashioned one out of a piece of piano wire, put it on the bichord about = a quarter inch from the bridge and the nasty sound was gone, gone, gone.</FONT></DIV> <DIV> </DIV> <DIV><FONT face=Arial size=2>If anyone has the formula for = longitudinal vibration interference, here's the data:</FONT></DIV> <DIV><FONT face=Arial size=2>Note is A2, speaking length is 1017mm, = core is .041, wrap is size 30 (.014) and exposed core is 12.7mm (1/2 in) at both = ends.</FONT></DIV> <DIV><FONT face=Arial size=2></FONT> </DIV> <DIV><FONT face=Arial size=2>I have had plans for building a device = to find out the frequency of an offending sound through using a tunable filter and a = tight fitting head phone floating around in the dark crevices of my kidneys = for some time.  I guess now is the time to pass it.</FONT></DIV> <DIV><FONT face=Arial size=2></FONT> </DIV> <DIV><FONT face=Arial size=2>Thanks guys for any = comments.</FONT></DIV> <DIV><FONT face=Arial size=2></FONT> </DIV> <DIV><FONT face=Arial size=2>Carl Meyer PTG assoc<BR>Santa Clara, Ca.</FONT></DIV> <DIV> </DIV> <DIV> </DIV> <DIV><FONT face=Arial size=2></FONT> </DIV> <DIV><FONT face=Arial size=2></FONT> </DIV> <DIV><FONT face=Arial size=2></FONT> </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=ilvey@sbcglobal.net = href="mailto:ilvey@sbcglobal.net">David Ilvedson</A> </DIV> <DIV style="FONT: 10pt arial"><B>To:</B> <A title=caut@ptg.org href="mailto:caut@ptg.org">caut@ptg.org</A> ; <A = title=pianotech@ptg.org href="mailto:pianotech@ptg.org">pianotech@ptg.org</A> </DIV> <DIV style="FONT: 10pt arial"><B>Sent:</B> Monday, October 03, 2005 = 8:05 AM</DIV> <DIV style="FONT: 10pt arial"><B>Subject:</B> pitchlock</DIV> <DIV><BR></DIV> <P>List,</P> <P> </P> <P>Sometime ago I was complaining about a new Pleyel upright with at = least 8 mismatched bi-chord bass strings.   I could'nt get a clean = unison and the octaves were impossible.  A few weeks ago I installed = some pitchlock clips to the offending bass strings and voila...much better = unisons and octaves.   I was going to change the bass = strings...  Definitely worth keeping in the tool kit.</P> <P> </P> <P>David I.<BR><BR></P></BLOCKQUOTE></BODY></HTML>