David, There are lots of variables we don't know here. For one, is it being played regularly, as in a student practicing hard? Playing serious music? Check plate bolts, and tap down a couple of string coils on the tuning pins. If the coils are unstable you can loose 1 whole tone (200c) easily - so they all need to be tapped down, or that 200c will drop over the next few years. The new strings are also likely unstable, so do a test. Measure a string in the mid-treble, then tap it down lightly or hook it up at all of the string bends. See how much it drops - if a lot (more than 10c), then the piano probably has very stiff wire that still needs to stabilize. You can speed this along if the customer is willing to pay you for your time, or you can just keep feeding it tunings. To get them stable, raise the pitch above normal by about the same amount that the sample string dropped. So use RCT in pitch raise mode, but if the sample string dropped 20c, also set RCT to 445 when tuning the treble strings to give extra compensation. Or, just treat it like a new piano and tune it a lot! I like to get the strings stabilized, though, as I feel the end result is a more stable piano. Don Mannino ----- Original Message ----- From: "David Trasoff" <david at davidtrasoff.com> To: <pianotech at ptg.org> Sent: Sunday, June 14, 2009 2:24 PM Subject: [pianotech] New Asian piano that will not hold a tuning I am wondering what ideas or experience people have concerning the possible reasons a new Korean-made piano seems to be incapable of holding pitch. It's a 5'3" Samick-made grand. It was tuned prior to delivery in early September 08 (I assume it was; I didn't do it). When I gave it its post-delivery service in September it had slipped 30-40¢. I pitch-raised and tuned it. By December the customer was complaining; I made another service call and found the piano again 30-40¢ flat. I again double tuned it (using the RCT pitch raise function) and left it on pitch. I tuned the piano again in the beginning of June and found the bass about 25¢ flat, the midrange from 10-15¢ flat to on pitch, and the high treble 80¢ or more flat! It seems pretty obvious that something is moving around in there, a bad glue joint in the frame? an improperly secured plate? I don't have the luxury of going back and making measurements or poking around (I'm not being paid to do that), but I'm interested in what other technicians think may be going on with this piano. I've recommended to the store that sold the piano that it be replaced, but I'd like to have some possible technical points regarding the apparent failure in the structure of this piano to discuss. Thanks, David Trasoff --- David Trasoff Professional Piano Service 4130 Verdugo View Drive Los Angeles, CA 90065 Tel: 323-255-7783 Fax: 323-313-1519 david at professionalpianoservice.com
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