Because of the key and the system flex , I believe that "synchronism" , or a very short follow-up is very well possible, assuming the hammer hit the string and is back in check in a very short moment, and the key did not bottom yet, for instance. Another possibility is that the key bottom first and the hammer is in check before the wave travel of the key is yet passed... The hammer impact also is generating a bump, (one in the string and one in the hammer pin) so we are yet there with 4 bumps in a very short time.) And so on, I will probably not dream of that tonight, so no chance I see the light since tomorrow ! The idea of these serial of bump reinforcing a wave going toward the tail of the piano pleases me a tad also. A similar effect partially occur on vertical pianos , seem to me (or part of the aforementioned) Isaac OLEG Ric say : > of course.... no way these can be in sync at all to begin with.. Still.... ya gota admit he had a seductive explanation there.... :) Cheers RicB A440A@aol.com wrote: >Bernard writes: > ><< the energy of the hammer returned to the backcheck and the energy of the >key to the keyframe become synchronous with the said 2 milimeters. If this two >blows are synchronized, there is a higher pulse wave running through the >instrument giving more additional energy to the string than when this two blows are >time offset (and may cause phase losses when reaching the string).<< > > Greetings, > According to Anders Askenfelt, the timing of these two events is dependant >on the force of the blow, so their synchronization is variable. In the >publication "Five Lectures", ( http://www.speech.kth.se/music/5_lectures/ ) it is >pretty clear that the hammer will return to the back check well after the key >has hit the bottom of its stroke on all but the softest blows. The stronger the >blow, the earlier the key bottoms in relation to everything else. > There are transient pulses that do travel back and forth through the >action as the hammer goes through its arc, but without contacting anything, the >backcheck seems to be isolated until after escapement. I am not convinced that >the distance from the tail of the hammer is as important as the interfacing >angle of tail to backcheck surface. There is certainly a feeling of contact when >the tail is grabbed suddenly by an acutely angled backcheck as opposed to the >longer path the tail makes when contacting a more parallel surface of the >backcheck. This seems to be no greater than the differences that can be felt with >different hardness of key end felt under the damper levers, though. >Regards, > >Ed Foote RPT >http://www.uk-piano.org/edfoote/index.html >www.uk-piano.org/edfoote/well_tempered_piano.html > >_______________________________________________ >pianotech list info: https://www.moypiano.com/resources/#archives > > > _______________________________________________ pianotech list info: https://www.moypiano.com/resources/#archives
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