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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