> dear Collegiate and Universitarianistic tuners, here at New York > University we have about 50 newish u1s, none over 10 yrs old and most > younger than 5. They break bass stgs. Yamaha claims that happens with > every other make of upright in a music school setting. I do not believe > them. Most of our u1s have over 1/2 dozen missing or replaced bass > strings (treble never break). Instead of believing anyone, try running a scale analysis for yourself. You'll find high bass tensions putting the percentage of breaking strength in the high 60%, to the low 70% by Sanderson's formula. This is obscenely high. I have a lot of Yamaha verticals in my clientele, and haven't had bass string breakage problems at all, but I suspect it's just because they aren't pounded hard and continuously. I'd recommend replacing wrapped strings with sets scaled to a lower break% rather than replacing the pianos, if they are otherwise doing the required job. I sure wouldn't go to Mapes for the rescaling. Ron N
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