John: I am enjoying this discussion a great deal. On shorter pianos (which is about all I tune...) I avoid using the wound strings for tests when I can help it. The partials are often wavery. This is another reason that I prefer the 6:4 test. On pianos like this the iH of the 6:4 5th *is *vastly different than the 3:2 5th. But the iH of the 6:4 5th is closer to the other tuning intervals than the iH of the 3:2 5th. (It might be more correct to say "the difference in iH".) So, I find it is easier to tune with the 6:4 5ths. In the lower part of the unwound tenor I am sure that this can result in a wide 3:2 5th and a narrow 6:4 5ths, but that is often the best compromise. Now back to my original question. You said that your 3:2 5ths beat at the same speed across the entire keyboard but that your 4ths increase in beat speed toward the treble, and that you use a wide octave. I don't think the cause of this phenomena is widely understood. It seems that it all depends on the octave stretch and the iH. The more octave stretch and iH, the more this phenomena will occur, I suppose even to the point where 5ths can become wide in the treble while the 4ths continue to beat faster. But when listening to 6:4 5ths, it may not be noticeable what the beat rate of the 3:2 5ths are doing. Can anyone confirm this? On Thu, Nov 6, 2008 at 8:33 AM, John Formsma <formsma at gmail.com> wrote: > As long as the inharmonicity of the 6:4 is not vastly different from the > 3:2, that's probably generally OK. But the M6-M10 is really easy to listen > to. You can always change the reference note to make the beats slower. > And, you're listening to for just a slight difference in beat speeds. > In the example of G#2-F3 and G#2-C4, let's say G#2-F3 beats at 6 bps. You'd > want to have G#2-C4 just slightly slower. If that beats 5 bps, then it's > too narrow. Assuming you can hear the 1/2 bps difference between chromatic > M3s and M6s, it's no problem to hear the difference in the M6-M10. > > My P4s are always around 1 bps in the F3-F4 area, but since I tend to pure > P5s, the P4s are a tad more than 1 bps. They're always closer to 1 bps than > 2 bps. They obviously increase in the upper midrange, but you can't really > hear them much past C5, so beyond C5, particularly in a musical context. > So, beyond the midrange. you are more concerned about octaves. > > As you say, to each his own, but I find that tuning 2:1 octaves up from the > midrange leads to an intolerably flat sounding treble. To overcome this > tendency, one can tune with slightly expanded double octaves and slightly > contracted octave-fifths within the DO. E.g., make F3-F5 beat the same as > A#3-F5. Continue that up all the way, and down all the way. This leads to > a well-balanced tuning, and it sounds great. But it all begins with the > proper foundation; i.e., the bearing or temperament. > > -- > JF > -- Regards, Jeff Deutschle Please address replies to the List. Do not E-mail me privately. Thank You. -------------- next part -------------- An HTML attachment was scrubbed... URL: http://ptg.org/pipermail/pianotech_ptg.org/attachments/20081106/e6337956/attachment.html
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