Hi Bob: Here is a little known bit of minutae. The 5:4 ratio which we use for contiguous M3rd beat rates is also just a round number for the number 2 raised to the 1/3 power which is 1.259952. 1.259952 1.25 5 The fraction -------- rounds off to ----- or --- 1.000000 1 4 Then if we wanted to get real persnickety, we could say that the number 2 in the original formula isn't quite right either since due to inharmonicity our octaves are not exactly 2:1 Hey, for all practical purposes the 5/4 ratio works just fine. Jim Coleman, Sr. On Thu, 16 Dec 1999 BobDavis88@AOL.COM wrote: > A440A@AOL.COM writes: > > > A third which has a 5:4 > > ratio is a Just third and doesn't beat at all. > > Ed, > You are right, of course, but the 5:4 mentioned here doesn't refer to the > ratio of FREQUENCIES within the third, but the ratio of beat RATES of > contiguous thirds - A3-C#4 beats 5/4 as fast (or mighty close to it) as > F3-A3. Sorry for the confusion. > Bob Davis >
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