Hi Richard: Well, I stand corrected again. This time so does Kent. We should have said the 8:6 relationship. It is there and can be heard. It is very easily measured. My D3-G3 measures 2.1 cents wide at that coincidence. It is easily heard in ghost tone fashion. Jim Coleman, Sr. On Sun, 14 Jun 1998, Richard Moody wrote: > > > > > ---------- > > From: Jim Coleman, Sr. <pianotoo@IMAP2.ASU.EDU> > > To: Billbrpt@aol.com > > Cc: pianotech@ptg.org > > Subject: Re: Inharmonicity in strings > > Date: Saturday, June 13, 1998 10:33 PM > > > > Hi again Bill: > > > > I stand corrected by Kent Swafford. You can hear the 8:3 relationship. > > > > Jim Coleman, Sr > > Actually I don't think you can HEAR the 8:3. If you can, what's the first > thing that strikes you about the beats? You can hear an 11th, but to > split a hair, I don;'t think the beats that are supposed to be there (from > the 8 and 3 partials) can actually be heard. > > To be truthful, I can hear the 8:3 on a synthesizer, and yes I did have > to check the math to make certain the rate was what I thought. This was > starting at a -- d" (a3--d5). Still they are pretty damn weak, and given > the difficulty (comparative) of hearing 4:3 fourths on the piano, I doubt > they could be heard at all there. > > I believe the original question was about sine waves having no partials > execpt the fundamental, and the implications of that in tuning. > > But to address the postulation... no coincedent partials--no beats... > consider the following.... > > These tests were conducted on an analog synthesizer, harpsichord type > patch,(tweeked to give clearest beats) with unlimited sustain. > > It can be demonstrated, that clear audible beats disappear out side the > simple ratios, (non doubled)(lowest numerators) of the intervals. > > For instance, a third, 5:4 with root at c# (3) beats 5.5 /sec. the tenth > at 5:2 with the F now at f' (4) beats the same. at 17th the ratio is > 5:1 the beat is the same. However at the 24th or c# - f'' (F 6) no beats > are readily descernable. In fact they seem vanish. Now there should be a > 10:2 but can they be heard enough to be usefull, if at all? There was > always a doubt if I was hearing any beats there. > > Consider the 5:3 ratio, the 6th. Observe the ratio is composed of 2 prime > numbers. Take f--d' (f 3 -- d4) Pert'near 8 bps, and very distinct. > What about f--d" (f3--d5) ? NO BEATS ! ! The nearest coincedent > partials would be 10--3. The beats should be doubled, but they are not > nearly (if at all) audible to hear that. > > Richard Moody > > >
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