Ric: Thanks much for your full response to my leading questions. We are very much in agreement regarding terms, conditions, and diagnostic ambiguities. And yes, terminations are complex beasts! Paul In a message dated 2/28/2009 6:30:51 A.M. Central Standard Time, ricb at pianostemmer.no writes: Hi Paul ricb at pianostemmer.no writes: I'm also aware that many believe that false beats are caused by rust on strings, general termination problems, variations in string thickness and density... etc. etc. Etc. indeed. The phrase "general termination problems" is of course too broad. Have you decided that the condition of the "termination" is not part of or one of the causes? Please elaborate. :-) P I suppose "general termination problems" is a bit broad... but that and the other etc's mentioned were not really the point. And one has to remember in these discussions what kind of "falseness" we are talking about. Wavering unsteady falseness that displays no clear period is not what I am referring to. It is that classic false beat... clear and so identical in sound to the beating two strings that are slightly out of tune display. One also has to define closely what the "termination" really is. Many would have it that the termination at the bridge is simply the bridge pin. I don't subscribe to that idea. The bridge pin and bridge surface form a combined clamp that terminates the string. For that matter it is entirely possible that the end acoustic result... that is to say what is accepted of the strings vibration by the bridge and soundboard assembly and sent out into the air, is significantly affected by the condition of the wood components involved at critical points relative to any given string. Remember we are talking about extremely small out of phase movements here needed to cause an audible false beat. Just where those occur in the entire chain is in my opinion an unanswered question. All my experiments tell me that the false beat we "hear" is the result of a combination of events in which the bridge itself is most definitely involved. It seems quite possible, if not outright probably to me that a string, isolated from the soundboard and bridge producing a false beat does not necessarily result in an audible false beat when coupled to the bridge and soundboard assembly. Conditions at the pin / notch and for that matter the wood immediately surrounding the pin along its full length... anything that can contribute an out of phase condition where in one phase one frequency is transmitted further on in the system and in another phase another frequency is transmitted can affect what in the end comes out into the air. Sometimes these things could cancel each other out... other times enhance each other or even cause multiple false beats... which is also observable btw. Everything stated here is perfectly in line with theory of coupled vibrating systems. All this is in line with the basic train of sound production as described by a couple of the authors in the 5 lectures and other related studies. Its easy to simply look at the string itself, or the bridge pin itself as the soul support and thereby the cause of this phenomena and assume the soundboard assembly faithfully reproduces everything exactly as it hits the bridge pin. But this is an oversimplified perspective in my view to begin with... and secondly we actually do know the soundboard / bridge assembly does not necessarily always do this. We just haven't looked closely enough at that side of things to see how it can get into the classic audible false beat. Given the statistics I've run into... and the basics of how vibrating components all combine to produce any given output for a complete vibrating system.... it seems to me that the reigning theory (ie the loose pin flag polling postulate) is simply not nearly complete enough and doesn't match the observable results of controlled experimentation. Cheers RicB **************A Good Credit Score is 700 or Above. See yours in just 2 easy steps! (http://pr.atwola.com/promoclk/100126575x1218822736x1201267884/aol?redir=http:%2F%2Fwww.freecreditreport.com%2Fpm%2Fdefault.aspx%3Fsc%3D668072%26hmpgID %3D62%26bcd%3DfebemailfooterNO62) -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://ptg.org/pipermail/pianotech_ptg.org/attachments/20090228/5ee33229/attachment.html>
This PTG archive page provided courtesy of Moy Piano Service, LLC