41 Equal Temperament - Interval Size

Interval Size

Here are the sizes of some common intervals (shaded rows mark relatively poor matches):

interval name size (steps) size (cents) midi just ratio just (cents) midi error
perfect fifth 24 702.44 Play 3:2 701.96 Play +0.48
septimal tritone 20 585.37 Play 7:5 582.51 Play +2.85
11:8 wide fourth 19 556.10 Play 11:8 551.32 Play +4.78
15:11 wide fourth 18 526.83 Play 15:11 536.95 −10.12
27:20 wide fourth 18 526.83 Play 27:20 519.55 +7.28
perfect fourth 17 497.56 Play 4:3 498.04 Play −0.48
septimal narrow fourth 16 468.29 Play 21:16 470.78 −2.48
septimal major third 15 439.02 Play 9:7 435.08 Play +3.94
undecimal major third 14 409.76 Play 14:11 417.51 Play −7.75
major third 13 380.49 Play 5:4 386.31 Play −5.83
inverted 13th harmonic 12 351.22 Play 16:13 359.47 Play −8.25
undecimal neutral third 12 351.22 Play 11:9 347.41 Play +3.81
minor third 11 321.95 Play 6:5 315.64 Play +6.31
tridecimal minor third 10 292.68 Play 13:11 289.21 Play +3.47
septimal minor third 9 263.41 Play 7:6 266.87 Play −3.46
septimal whole tone 8 234.15 Play 8:7 231.17 Play +2.97
whole tone, major tone 7 204.88 Play 9:8 203.91 Play +0.97
whole tone, minor tone 6 175.61 Play 10:9 182.40 Play −6.79
lesser undecimal neutral second 5 146.34 Play 12:11 150.64 Play −4.30
septimal diatonic semitone 4 117.07 Play 15:14 119.44 Play −2.37
diatonic semitone 4 117.07 Play 16:15 111.73 +5.34
septimal chromatic semitone 3 87.80 Play 21:20 84.47 Play +3.34
chromatic semitone 2 58.54 25:24 70.67 −12.14
28:27 semitone 2 58.54 28:27 62.96 −4.42
septimal comma 1 29.27 Play 64:63 27.26 Play +2.00

As the table above shows, the 41-ET both distinguishes between and closely matches all intervals involving the ratios in the harmonic series up to and including the 10th overtone. This includes the distinction between the major tone and minor tone (thus 41-ET is not a meantone tuning). These close fits make 41-ET a good approximation for 5-, 7- and 9-limit music.

41-ET also closely matches a number of other intervals involving higher harmonics. It distinguishes between and closely matches all intervals involving up through the 12th overtones, with the exception of the greater undecimal neutral second (11:10).

Read more about this topic:  41 Equal Temperament

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