---------------------- multipart/alternative attachment Sergio, (First of all, don't worry about your English. It is fully comprehensible to us. I am always amazed by how well many Europeans speak and write the English language. I know it simply a matter of education, but when I was in school it was almost considered un-American to study any other language. Fortunately, that has changed in past years.) You have basically three problems. None of which are going to be easy to solve. In fact, without doing some major modifying of the original plate and soundboard assembly, you're not going to be able to really solve them at all! You might be able to make them a bit less bad, however. 1) The weak spot in the middle-treble section. This weak spot (what I, and many others in this country, call the "killer octave") has two causes. First the stringing scale is not all it could be through this region. To solve this problem, however, would require making a new bridge cap and repining it to incorporate the different string lengths dictated by a new design. Second, there are problems with the design of the soundboard in this piano. (Not to single out Steinway, most -- if not all -- other large grand pianos share these problems.) The killer octave region can be greatly improved -- in fact, it can be improved so much you'll wish you had at least 70 or 72 dampers on the piano -- but to do so requires replacing the soundboard with one of a different design. 2) The soft V-bar. It sounds as if the V-bar on this plate may be too soft for its intended function. There are only two common reasons why this V-bar should be so badly grooved in a piano built this recently. First, and probably most common, is mis-treatment by service technicians. The second is that the iron may simply be too soft. It the problem is simply sloppy servicing then reshaping it will solve at least that part of your problem. At least temporarily. If, however, the metal is simply too soft the only certain solution I that I am aware of is to remove the plate, very carefully grind a U-shaped groove along the center of the V-bar and insert a mild steel rod to act as the string termination. 3) The buzzy strings. This problem is characteristic of pianos using the so-called "tuned-aliquot" stringing system at the front string termination. The string deflection angle across the V-bar is not sufficient to adequately terminate the motion of the vibrating string. Hence, some of the energy is allowed to bleed (transfer) from the speaking portion of the string to the string segment between the V-bar and the counterbearing bar. This problem can be alleviated, but usually not illuminated, by careful shaping of the V-bar AND the counterbearing bar. Since the string segment between the V-bar and the counterbearing bar in this design is actually a "speaking" segment itself it is sensitive to the shape and contour of BOTH the V-bar and the counterbearing bar. It is not enough to simply remove the grooves in these bars. You have to verify that the radius of both are correct. The radius of each should be no greater than 1.5 mm in the lower V-bar section and should decrease to 0.75 mm in the top section. (In early 1995 I published an article in the Piano Technicians Journal on this subject. With this article was an illustration showing the more-or-less ideal shapes for these bars.) As far as the buzzy strings are concerned, it is best to try to control them at their source than to try to dampen them out with felt. Since this system is designed to allow some percentage of the speaking strings energy to bleed past the V-bar, damping it will always result in a shorter sustain. Since sustain is already a problem in these sections, this is not a good solution. As far as string down bearing is concerned, the best way to determine that is to measure the string deflection angle across the bridge (with the strings at tension). On most pianos there should be between 0.5° and 0.75° at the start of the lower treble section and 1.0° and 1.5° at the top of the upper treble section. Whatever you measure within these ranges will be acceptable. I'm sure I've probably generated more questions than I've answered here. And this may well be more involved in the piano than you want to get. But you can waste a lot of time trying to overcome basic design features of the piano, if you're not careful. Regards, Del --------------------------------------- SERGIO BRUNELLO wrote: > Now to the question, I hope somebody can help me.I have a problem with a Steinway e sons mod. D > made 1990. It is a very good instrument but it has a weak spot in the middle-treble section > (F57-F69). The strings give a buzzy noise ( we say "frezzle strings"), coming from the capo bar's > duplex scale. I checked the piano and I note that a lot of string was changed (breaking problem) > by other technicians, and come me the doubt that wasn't a good work. The capo bar underface showed > a lot of furrows in the strangest positions. I decide to change all the middle-treble sector's > strings with the right string size and to make smooth the capo bar underface. The bridge's string > pressure was correct (by my knowledge; please can you give me this pressure information so I can > compare if mine are correct ?).After the restringing and tuning, I checked the hammers striking > point that was correct.All this work was useless the duplex scale still buzzers.I tried with a > more soft voicing, a little better but not enough.So at the end I decided for what I wanted to do. > I put a felt strip among the duplex scale's strings. OK the buzzer stopped but the sound falled in > brightness. Associated with the more soft voicing the sector is no comparable with the others.I am > displeased with the work's results. Someone have already had this problem ? There are some more or > better work to do? I'll be grateful to get some suggestions. Sergio BrunelloTreviso, Italy > ---------------------- multipart/alternative attachment An HTML attachment was scrubbed... URL: https://www.moypiano.com/ptg/pianotech.php/attachments/86/a3/8c/d8/attachment.htm ---------------------- multipart/alternative attachment--
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