<!doctype html public "-//W3C//DTD W3 HTML//EN"> <html><head><style type="text/css"></style><title>Re: Yamaha Tuning Instability</title></head><body> <div>Hi all,</div> <div><br></div> <div>At 10:16 AM -0500 23/9/02, jolly roger wrote:</div> <blockquote type="cite" cite>Hi Terry,</blockquote> <blockquote type="cite" cite>. . . Some Yamaha models tend to go a little sharper than average, at the end of the long bridge, with high humidity swings, yet the bass strings are much more stable.</blockquote> <div><br></div> <div>Indeed, the tension percentage of breaking strain deviation<font color="#0000FF"> (downwards)</font> at the 'hockey stick' end allows for humidity swings to play havoc with the pitch<font color="#0000FF"> (especially so, if there is also too much down bearing)</font>. The swings away from the piano's nominal pitch tend to be proportional to the swing in the 'percentage of break' away from the nominal tension - moving in the same direction as the change in relative humidity levels. I first discovered this 'scaling disease' in the late seventies when I began tuning a bunch of C7 Yamahas on a weekly basis for various Sydney recording studios. If one was out there were all out. If one was straight they were generally all straight<font color="#0000FF"> (so the effect could not be attributed to different pianists, since their effect would be random)</font>. With the help of my pocket calculator<font color="#0000FF"> (in those days)</font> I discovered that percentage of breaking strain deviation was the culprit.</div> <div><br></div> <div>Relatively, the bass tends not to move in Yamahas since they are typically scaled at very high tension immediately after the last plain wire. It is just not necessary nor desirable to scale at over 60 % brk. str.</div> <div><br></div> <blockquote type="cite" cite> The octaves across the tenor break will  become noticeably wild.</blockquote> <div><br></div> <div>Again a symptom of wild % brk fluctuations.</div> <div><br></div> <blockquote type="cite" cite> Before installing Damp chasers, some of our University studios have a C3 and G2 in them.   It was a constant problem trying to keep them together. After installation complaints stopped.</blockquote> <div><br></div> <div>Absolutely, minimising the humidity swings will minimise the deleterious effect of the ordinary scaling.</div> <div><br></div> <div>Wonderful possibilities still await us in the world of scaling. Its such a shame that the major manufacturers won't investigate what's possible. Sticking with tradition and history seems to be the easy option. Some manufacturers still seem content to copy the conceptions of a century ago in an attempt to create a 'new' model, 'trotting out' the same old stuff again while making big and unjustified noises about their scaling and design attributes - lamentable stuff.</div> <div><br></div> <div>I look forward to a possibly-not-too-distant future, where the recalcitrants might be forced to adopt a new standard.</div> <div><br></div> <div>Regards to all,</div> <div>Ron O.</div> <div><br></div> <div>PS. I still read the posts even if I don't contribute much. Things are still tight down here in Sydney, but they may well improve very soon - thank you to those of you who have sent private posts of support.</div> <x-sigsep><pre>-- </pre></x-sigsep> <div>_______________________<br> <br> OVERS PIANOS - SYDNEY<br> Grand Piano Manufacturers<br> <br> Web: http://overspianos.com.au<br> mailto:info@overspianos.com.au<br> _______________________</div> </body> </html>