Bidic comma

Interval information

Ratio	327680/321489
Factorization	216 × 3-8 × 5 × 7-2
Monzo	[16 -8 1 -2⟩
Size in cents	33.02189¢
Name	bidic comma
Color name	saruruyo unison, srry1, saruruyo comma
FJS name	[math]\displaystyle{ \text{P1}^{5}_{7,7} }[/math]
Special properties	reduced
Tenney norm (log2 nd)	36.6163
Weil norm (log2 max(n, d))	36.6439
Wilson norm (sopfr(nd))	75
Comma size	medium
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327680/321489, the bidic comma, is a 7-limit comma measuring about 33 cents and is the difference between a stack of two 64/63's and a single 81/80. Tempering out this comma generally means that 64/63 is half the size of 81/80 and that 5120/5103 (the argent comma) is mapped as a negative interval.

Etymology

The name was given by Tristan Bay in 2025 as a reference to bidia temperament having the tuning quirks described above as a result of this comma being tempered out.