Katsura-san, The problem you are facing is that each piano is unique. Yes, you can put in approximate stretch values for typical grands or even specific models of a particular manufacturer. When you do that, and IF the person doing the tuning is able to match your pitch for each note, they will still not have an expert tuning. Here's the secret. Each string creates a set of partials when struck. These partials are not integer multiples of the fundamental. In general, each higher partial is slightly sharper than the previous partial. The secret to good sounding tunings is to maximize the matches between all the important partials of each string to all the other strings within the constraints of somewhat equal temperament (12th root of 2). So, to match an expert piano technician, your tuning program should measure each partial of each string, and then do a best fit of the most important partials (loudest, etc) so that the piano sounds as smooth as you can get it. This is what aural tuners do, and that is also what the best electronic tuners strive to do. To see how others have solved this problem, go to their web sites. See www.veritune.com/, or http://www.tunelab-world.com/ or http://www.accu-tuner.com/. There are other professional electronic tuners out there as well. My recommendation is that if you are really serious about making a professional tuning program, you should join the Piano Technicians Guild and learn about the instrument. You can take tuning classes at many local, regional and national conventions. The National convention is June 15-19 in Kansas City. Good luck, Doug Knabe Dallas Hidetomo Katsura wrote: > thanks. i forgot to mention that i knew about the stretch tables on > the Peterson 490ST manual and three piano model specific stretch > tables at precisionstrobe.com (fyi, i did use google). > > i'm looking for something more specific to each piano manufacturer > and model (like the ones at precisionstrobe.com). > > katsura > > On Apr 23, 2005, at 2:35 PM, Benny L. Tucker wrote: > >> This pdf manual for a Peterson Strobe Tuner is available for >> download at the >> link below. It lists the offsets for the fundamental frequencies for >> several >> different piano styles. I use this tuner myself to intonate guitars >> with. >> You may have to copy and paste the link into your browser if it gets >> chopped >> up in the email. >> Hope this helps. >> >> http://www.petersontuners.com/support/pdfmanuals/PDF%20Manuals/ >> Strobe%20Tune >> rs%20-%20True%20Mechanical/AutoStrobe/AutoStrobe%20490ST/ >> 490stenglish.pdf >> >> Benny L. Tucker >> Yamaha Factory Tuner >> Precision Piano Tuning & Repair >> Thomaston, Ga. >> >> >> i see. it's my own ETD i developed based on the popular requests from >> my Strobe Tuner users. >> >> Piano Tuner 1.0 for Mac OS X >> >> http://www.versiontracker.com/dyn/moreinfo/macosx/26163 >> >> my stretch offset table data format is just a text file with note names >> and offsets and looks like this: >> >> "A0"="-20.000"; >> "Bb0"="-19.000"; >> "B0"="-18.000"; >> "C1"="-17.000"; >> "C#1"="-16.000"; >> "D1"="-15.000"; >> >> katsura >> >> >> >> >> _______________________________________________ >> pianotech list info: https://www.moypiano.com/resources/#archives >> > > _______________________________________________ > pianotech list info: https://www.moypiano.com/resources/#archives >
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