<!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 5.50.4134.600" name=GENERATOR> <STYLE></STYLE> </HEAD> <BODY bgColor=#ffffff> <DIV><FONT color=#000080 size=2></FONT> </DIV> <BLOCKQUOTE dir=ltr style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; = BORDER-LEFT: #000080 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=Richard.Brekne@grieg.uib.no href="mailto:Richard.Brekne@grieg.uib.no">Richard Brekne</A> </DIV> <DIV style="FONT: 10pt arial"><B>To:</B> <A = title=pianotech@ptg.org href="mailto:pianotech@ptg.org">pianotech@ptg.org</A> </DIV> <DIV style="FONT: 10pt arial"><B>Sent:</B> December 03, 2001 12:04 = PM</DIV> <DIV style="FONT: 10pt arial"><B>Subject:</B> Re: Negative bearing (long)</DIV> <DIV><FONT color=#000080 size=2></FONT><FONT color=#000080 size=2></FONT><BR></DIV>Delwin D Fandrich wrote: <BLOCKQUOTE TYPE="CITE"> <BR>The understanding of soundboard = function has moved a bit beyond the purely <BR>empirical--even beyond 90% empirical--though certainly not to the stage of <BR>pure science = either. Still, techniques such as modal analysis have enabled <BR>the study = of soundboard function at a level not even dreamed of even thirty = <BR>or forty years ago. It is my hope that before I pass from the scene that = <BR>this understanding will be still some closer to scientific and much less <BR>reliant on the empirical. <P>Del</P></BLOCKQUOTE> <P><FONT color=#000080 size=2></FONT><FONT color=#000080 size=2></FONT><BR>Been reading and weeding through and find much = that is interesting, but this comment caught my eye and I must admit is = confusing. I wrote about modal analysis a year and a half back and you came out and = said it was basically useless in designing soundboards, since the conditions = for measurement are different then the conditions for full strung, and if = done full strung well the deed is already done so to speak... further you = pointed out then that you meant that there was no reliable way of forcasting = said changes. <BR>  <P>From the fall of 1999  where we were in a disscussion about = impedance matching, and the usefullness of modal analysis came up I submit the = following three posts. </P></BLOCKQUOTE> <P dir=ltr><FONT color=#000080 size=2></FONT>  <P dir=ltr><FONT color=#000080 size=2>Pease go back and read what = I wrote, to wit:<BR>    "One of the problems I have with most of the = testing I have seen on the piano soundboard is that it was done on an unloaded = board and is, therefore, largely meaningless."</FONT></P> <P dir=ltr><FONT color=#000080 size=2>There is no rule = that states modal analysis cannot be done with good results on a loaded board, complete = with strings. It's just more difficult. Tests with unloaded boards are, in my = opinion, largely meaningless. It becomes something else when done in a = real world setting complete with strings and loading. Again, my experience is = some limited. I have only used the technique to analyze one soundboard = assembly and it did lead to some considered changes in the ribbing which--again, in = my opinion--improved the performance of the piano involved. </FONT></P> <P dir=ltr><FONT color=#000080 = size=2>Del<BR><BR></P></FONT></BODY></HTML>