Calculated as the 72nd root of 2 -- 72√2, or 2(1/72) -- an irrational proportion with the approximate ratio of 1 : _, and an interval size of exactly 16 2/3 cents. It is the size of one degree, and thus the basic "step" size, in the 72-edo (or 72-tET) scale.
Several composers and theorists have advocated 72-edo tuning, including Ivan Wyschnegradsky, Alois Hába, Franz Richter Herf, Ezra Sims, Joe Maneri, Paul Erlich, and Joe Monzo.
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