I'm reading the mail and discussion between Ric Brekne and Fred Sturm. The Conn stroboscope that I believe Robert Young used for his measurements was pleaty good for showing the inharmonicity trends that he discusses, despite the fact that we can make more accurate measurements now. There is the fact that a string in a real piano is subject to the characteristics of the piano's acoustical system being reflected back into it. Regarding bass strings: Fred mentions anomalies in inharmonic ladders that Dean Reyburn has discussed. I have not seen Dean's work, but I can say those anomalies are very real. They are NOT from faulty measurements. They come form the fact that it is IMPOSSIBLE to wind a PERFECT bass string. The very slightest irregularity of ANY kind in the winding or core wire will cause it. I have been measuring and plotting inharmonicity curves of bass strings for nearly two years now, using a monichoord I designed just for that purpose, and some state-of-the-art analysis programs. The advantage of the heavy, rigid monochord is that it is very stable, and there is no bridge/soundboard combination to couple energy away or reflect it's own characteristics back into the string. Consequently, the sustain time of a big top-quality bass string on my monochord is like two to four minutes for a 60 dB decay - many times longer than in a piano. If it were in a vacuum, the ring-down time would be longer than that, but that's impractical and unnecessary. Ric also raises the question of density-vs-tension. I wonder about that too. It seems to me that could be inferred from Poisson's ratio, but so far I have not followed up on it. I have measured a very slight negative effect of tension on longitudinal wave velocity in piano wire. This is very, very slight, but it's there. I mention this in the second paragraph on page 28 of my book, "Longitudinal Modes in Piano Strings". One would think that under tension, the density would, if anything, decrease. But if that were the sole cause of a change in longitudinal wave velocity, the effect would be positive rather than negarive, unless it were offset by something else, which I think it is. Right now, these are open questions, and I am still looking for the answers. Also, if someone can direct me to Dean Reyburn's work, I would really like to read it. Sincerely, Jim Ellis
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