Ric, Are you saying that inserting a brass bushing (what is that? like a pin?) under the string in the middle of the bridge will never cause a false beat or that sometimes it never causes a false beat? That replacing a bridge pin on a string that is clean always stays clean even if the new pin is smaller and loose? David Ilvedson, RPT Pacifica, CA 94044 ----- Original message ---------------------------------------- From: "Richard Brekne" <ricb at pianostemmer.no> To: pianotech at ptg.org Received: 2/27/2009 6:50:22 AM Subject: Re: [pianotech] Additional Information Regarding False Beats > I am a frequent reader of this list and it has been a great source >of information in my studies. Thank you all for generously sharing your >knowledge. > -Zane Omohundro > >Hi >Reading the many opinions on this as so many other piano subject matter >is sometimes almost as entertaining as observing the various opinions >there are relating to Cosmology. You will find the greatest part of the >"information" available is really opinion and conjecture and there is >some smaller amount of bold faced pure facta. >A recent article in the Journal by Jim Ellis with contributions from Del >Fandrich and a couple others takes the string isolated from the effects >of the soundboard and bridge assembly and shows some interesting >results. John Delecour posted a link to a paper done on the subject >matter some time back. The Five Lectures, tho not directly relevant are >worth looking through as they get into some of the possible ways the >soundboard and bridge assembly can get into the false beat picture. >http://www.speech.kth.se/music/5_lectures/contents.html >I have done quite a bit of informal experimenting myself on the matter, >tho have not published a formal study (yet) and found that the >observable relationship between loose pins and occurrent classic false >beats is from a statistical point of view is actually quite random. At >the same time the addition of substances such as cellulose lacquer, CA >glue, epoxy and some others to the bridge pin holes has a statistically >significant impact on the reduction of these false beats. Drawing >conclusions as to why this happens is another matter and I maintain >there is no hard evidence to support any of the conclusions usually made >and voiced. >Interestingly, relating to the loose pin argument frequently floating. >You can take 10 very clean sounding strings, replace the bridge pin with >an undersized pin creating a very loose pin situation and find that none >of these same develop false beats. You can also simulate the stated >condition that supposedly causes the false beat (flag poling pins) by >inserting a 2 mm brass bushing under the string at the center of the >bridge extending back to the distal bridge pin and find no development >of false beats. You can also experience that a false beat IS evident and >either of the alterations above actually eliminate it.... tho this >doesn't seem to happen more then a small percentage of the time. >I don't pretend to have the answers as to why things behave the way they >do.... but my approach to this kind of thing is to directly observe >various isolated conditions to see if the observable results match up >with what those who rely on some understanding of theory claim should >happen. >Cheers >RicB
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