Diminished second
Size in different tuning systems

Diminished second

Section Title: Size in different tuning systems
Table Section Text: None

Tuning system	Definition of diminished second	Size

Difference between semitones	Equivalent to	Cents	Ratio

Pythagorean tuning	m2 − A1	Opposite of Pythagorean comma	−23.46	524288:531441

1/12-comma meantone	m2 − A1	Opposite of schisma	−1.95	32768:32805

12-tone equal temperament	m2 − A1	Unison	0.00	1:1

1/6-comma meantone	m2 − A1	Diaschisma	19.55	2048:2025

5-limit tuning	S3 − S2

1/4-comma meantone	m2 − A1	(Lesser) diesis	41.06	128:125

5-limit tuning	S3 − S1

1/3-comma meantone	m2 − A1	Greater diesis	62.57	648:625

5-limit tuning	S4 − S1

19-tone equal temperament	m2 − A1	Chromatic semitone (A1 = m2 / 2)	63.16	2^(1÷19):1

Sentence(s)

In Pythagorean tuning a negative size (−23.46 cents), equal to the opposite of a Pythagorean comma.

final_sentence: In Pythagorean tuning a negative size (−23.46 cents), equal to the opposite of a Pythagorean comma.