Kevin, Your report of your treatment of the front duplex in a S & S M is most interesting and challenging. Although I've spent many years developing duplex tuning technology, 98% of it has been on rear duplexes so I don't know how valuable my comments may be to you. However in the interest of your client's satisfaction and our edification I'll offer a few thoughts hoping that perhaps one on them may be useful. The "proper fix" should be when the duplex scale of that particular unison produces a fundamental tone which is a partial of the speaking length. The front duplexes are pretty short, so they're way up there, e.g. triple octaves. Since front duplexes are for the most part nonadjustable you may have to resort to muting if no other solution can be found. The fact that the disturbance occurs, however, on only a few notes suggests that the problem may not be the duplex at all. The appearance of the problem after the piano was tuned is really the only time when the duplex effect can be perceived. Everything else has to be correct. It is a finishing touch to the tone. "All the other stuff" must be in place, strike point, bearing, hammers, strings, etc. before the subtlety of the duplex effect can create the "singing tone" Steinway speaks about in his patent. Your mention of the phrase " long waste end notes" may be misleading. Nothing is really wasted. The lengths of string beyond the agraffes are not really wasted, otherwise we would be terminating strings at the bridge pin, and that doesn't work in even the smallest ukelele. It may not seem physically possible at first thought, but the string is totally alive from hitchpin to tuning pin. There is life after the agraffe. Exactly how much, I can't say but the longitudinal waves produced by the striking of the hammer on the string are affected by the distal portions of the string, the non speaking lengths which you refer to as "waste". Personally I don't think there is any waste. In my view the actions of seating the strings was exactly on the money. The result of doing some needling on the crown, which had an ameliorative effect suggests that voicing may be the answer. I don't blame you for disliking having to deal with these issues on an expensive piano, or for that matter any piano. But until factories who manufacture pianos with duplex scales can solve the problem of achieving the best sound for their piano by the optimum placement of their duplex scale oliquot or contiguous harmonic bridge, we may have to deal with it, just as the buyer of a new Mercededs or jaguar has to take his vehicle to his own private mechanic to fine tune the vehicle. ( I may be wrong on this because I've never bought a new Mercedes or Jaguar) There is one little anecdote on this subject that you might like to hear. At a National Convention some years ago I sat next to a Yamaha technician at our Banquet. i had tested the magnificent Yamaha grand in the exhibit, and found that the duplex scales were all muted. But after loosening the braids on a few unisons i found that the duplex scale was not in tune with the speaking length. I asked the yamaha technician why they muted the duplexes. His answer was, as well as i can recall: We don't tune them, we mute them" Well, Yamaha is selling a great deal of great pianos so it may be "moot" to discuss the "mute" . Hope this has been of some help. I'd be anxious to hear of your further progress in this matter. Duplexdan@aol.com
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