<!doctype html public "-//W3C//DTD W3 HTML//EN"> <html><head><style type="text/css"></style><title>Re: Soundboard Crown measurement and evaluation</title></head><body> <div>Hello John,</div> <div>At 3:44 PM -0500 25/11/05, John Alsina wrote:</div> <blockquote type="cite" cite><br></blockquote> <blockquote type="cite" cite><font face="Arial" size="-1">Your recent post describes re-crowning the soundboard in a relatively new instrument.</font></blockquote> <blockquote type="cite" cite><font face="Arial" size="-1">Would this technique be worth considering for older instruments?</font></blockquote> <div><br></div> <div>Very much so, provided that the overall scope of required repairs makes it a viable proposition. The thing about 20-30 year old Kawai, Steinway and Yamaha pianos in particular is that there are thousands out there in the field, many of them have sunken sound boards. If you find this hard to imagine, just hold a 150 mm metal rule under the bridge position on the under side of the board (and for some pianos at the feathered rib ends also). The rule can be rocked. Sure, they might sound OK now in some cases, but some will sound very ordinary and rib extensions will fix the problem provided the instruments are otherwise structurally sound. You will even find pianos on showroom floors with inside out boards which already are exhibiting signs of significant shortness of tone.</div> <div><br></div> <blockquote type="cite" cite><font face="Arial" size="-1">For example: an 80-year-old compression crowned instrument whose soundboard is visually</font></blockquote> <blockquote type="cite" cite><font face="Arial" size="-1">in good condition but flat in the mid-treble, resulting in short sustain in that range.</font></blockquote> <blockquote type="cite" cite><font face="Arial" size="-1">On the one hand, the SB might already be crushed and "dead."</font></blockquote> <div><br></div> <div>Certainly the grain in the panel will be crushed, relative to its condition when new, but it won't be dead if you fit rib extensions. The stiffness and tonal improvement is astounding. One of the limitations with older instruments would be where the finish on the underside of the board has deteriorated. The top surface and set bolt holes can be refinished, but the area over the belly rail will be almost impossible to access for re-coating.</div> <div><br></div> <blockquote type="cite" cite><font face="Arial" size="-1">On the other hand, if new built-up ribs could provide sufficient springiness by themselves,</font></blockquote> <blockquote type="cite" cite><font face="Arial" size="-1">the soundboard would only have to serve as a diaphragm, so perhaps even a dead SB would do.</font></blockquote> <div><br></div> <div>Exactly, just as it does with rib crowned and supported new soundboards.</div> <div><br></div> <div>Provided the original ribs are firmly glued to the panel and the panel is firmly glued to the rim, I don't think it matters how dead the board is, it will response very well to rib crowning. What we are creating is a rib-supported assembly which originally was compression crowned. It it will work very well.  We're currently charging about A$15K - 16 to build a new soundboard and bridges, while the last two rib extension jobs cost the clients around A$5K (US$3.6K) each for the rib extension part of the work.</div> <div><br></div> <div>At present it takes us a whole week to do a full rib extension job. The preparation, particularly the removal of original rib height with a rasp, involves hard back-breaking work, but the excellent result makes it all worthwhile.</div> <div><br></div> <div>Best regards,</div> <div>Ron O.</div> <x-sigsep><pre>-- </pre></x-sigsep> <div><font face="Times New Roman" size="+1" color="#0000FF"><b>OVERS PIANOS - SYDNEY</b></font></div> <div><font color="#000000"><i>   </i></font><font color="#0000FF"><i>Grand Piano Manufacturers</i></font><font color="#000000"><br> _______________________</font></div> <div><font size="-2" color="#000000"><br> </font><font color="#000000">Web http://overspianos.com.au</font></div> <div><font color="#000000">mailto:ron@overspianos.com.au<br> _______________________</font></div> </body> </html>