Bradley, Jason, and Mike.. Thought I might update you a bit. Mike went and graphed the data I posted the other day showing the comparison between RCT's curve and what I came up with. Course mine was based on a simple linear spaceing of the range D3 to A4 which was itself tuned as a perfect 12th. Today I took the same perfect 12th, and then set A3 such that it was slowed relative to D3, and just a bit wider relative to A4. Turned out about 0.3 bps against D3 and somewhere in between a 6:3 and a 4:2 octave with A4. Then instead of useing Tunelabs 2 point linear curve for the 12th, I used all three frequencies (again read in from the 3rd partial of each) and used the 3 point quadratic interpolation Robert Scott built into Tunelab 97. This results in the same kind of basic curve that the RCT creates, and since notes outside the temperament are all tuned as perfect 12ths the curve just continues much in the same manner as the linear curve did, but with a smoother bend around A4. Bradley's graphing of how this would affect the different octave types would be interesting to see. I bet the results would be a bit different, same basic tendencies but curves bent a bit differently. Since his curves are theoretical based on measured inharmonicities I'll leave it to him to repeat the graph if he has time. I will try later on this week to measure a piano tuned thus note for note. I will also try and post the 3rd partials numbers I have from todays tuning, a brand spanking new Steinway D at Edvard Griegs home and museum that was to be used for a masters degree concert this evening. Cheers RicB Richard Brekne RPT NPTF Griegakadamiet UiB
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