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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>You might need html to view this.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Below is a chart that I use for soundboard analysis. Measurements are taken before and after taking the tension down. Crown sections are measured between the ribs using a string stretched as far as possible and a wedge gauge (very low tech). I try and correspond the measurement of the crown with the downbearing measurements in terms of location. An analysis of the soundboard rib design can also be made using the rib dimensions—I haven’t done that yet. Downbearing measurements are Lowell gauge readings. Note that .0175 corresponds to about 1 degree. <o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I won’t tell you what my conclusion was about this soundboard but you might be able to guess. (Steinway AIII)<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Question to ponder: Why would it be that although there is a positive change in downbearing when the tension comes off there is no apparent change in measured crown? Also note (not included in the data below) that when measuring the change in distance from the struts to the bridge in the upper end of the piano (from about rib #6 to the top) the average change was about 1 mm (the board rose about 1 mm). <o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>BTW this board had received a lot of shimming perhaps with the idea of restoring crown??? What do you think?<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Rib# Crown DB w-ten/wo Rib L H W (mm)<o:p></o:p></p><div style='mso-element:para-border-div;border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 1.0pt 0in'><p class=MsoNormal style='border:none;padding:0in'>Or section w-ten/ wo-ten<o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p><div style='mso-element:para-border-div;border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 1.0pt 0in'><p class=MsoNormal style='border:none;padding:0in'>1 2/2 .006/.015 600 17 28<o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p><div style='mso-element:para-border-div;border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 1.0pt 0in'><p class=MsoNormal style='border:none;padding:0in'>2 2/2 .006/.015 790 20 27<o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p><div style='mso-element:para-border-div;border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 1.0pt 0in'><p class=MsoNormal style='border:none;padding:0in'>3 2/2 .009/.012 940 20 27<o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p><div style='mso-element:para-border-div;border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 1.0pt 0in'><p class=MsoNormal style='border:none;padding:0in'>4 1.5/2.5 -.006/.003 1040 20 27<o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p><div style='mso-element:para-border-div;border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 1.0pt 0in'><p class=MsoNormal style='border:none;padding:0in'>5 0/.5 -.003/.003 1080 22 27<o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p><div style='mso-element:para-border-div;border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 1.0pt 0in'><p class=MsoNormal style='border:none;padding:0in'>6 0/0 -.009/.006 1120 21 27<o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p><div style='mso-element:para-border-div;border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 1.0pt 0in'><p class=MsoNormal style='border:none;padding:0in'>7 0/0 .006/.018 940 21 26<o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p><div style='mso-element:para-border-div;border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 1.0pt 0in'><p class=MsoNormal style='border:none;padding:0in'>8 0/0 .006/.021 660 20 25<o:p></o:p></p></div><p class=MsoNormal> <o:p></o:p></p><div style='mso-element:para-border-div;border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 1.0pt 0in'><p class=MsoNormal style='border:none;padding:0in'>9 0/0 .006/.027 560 20 18 <o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p><div style='mso-element:para-border-div;border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 1.0pt 0in'><p class=MsoNormal style='border:none;padding:0in'>10 0/0 .018/.042 390 18 23<o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p><div style='mso-element:para-border-div;border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 1.0pt 0in'><p class=MsoNormal style='border:none;padding:0in'>11 0/0 .022/.045 340 17 23<o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p><div style='mso-element:para-border-div;border:none;border-bottom:solid windowtext 1.0pt;padding:0in 0in 1.0pt 0in'><p class=MsoNormal style='border:none;padding:0in'>12 0/0 .025/.050 270 16 23<o:p></o:p></p></div><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>David Love<o:p></o:p></p><p class=MsoPlainText>www.davidlovepianos.com<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText><o:p> </o:p></p></div></body></html>