6:7:8:9
6:7:8:9 is a subminor add-4 chord in the 7-limit and the 9-odd-limit. In other words, it has a shape similar to a minor add-4 chord, but with a subminor third instead of a minor third.
| Chord information |
It can be constructed by stacking the intervals 7/6, 8/7 and 9/8 in that order, making it a stack of three consecutive superparticular intervals.
It is a subset of 5afdo. It is very approximated very well by 36edo, making it one of the most important consonant tetrads in 36edo harmony.
| Edo | Steps | Cents (¢) | Absolute errors (¢) | RMS (¢) | RMS (%) | |
|---|---|---|---|---|---|---|
| ▶ | 10 | 0 2 4 6 |
0.00 240.00 480.00 720.00 |
0.00 -26.87 -18.04 +18.04 |
17.27 | 14.39 |
| ▶ | 12 | 0 3 5 7 |
0.00 300.00 500.00 700.00 |
0.00 +33.13 +1.96 -1.96 |
14.41 | 14.41 |
| ▶ | 14 | 0 3 6 8 |
0.00 257.14 514.29 685.71 |
0.00 -9.73 +16.24 -16.24 |
12.23 | 14.27 |
| ▶ | 17 | 0 4 7 10 |
0.00 282.35 494.12 705.88 |
0.00 +15.48 -3.93 +3.93 |
7.26 | 10.28 |
| ▶ | 19 | 0 4 8 11 |
0.00 252.63 505.26 694.74 |
0.00 -14.24 +7.22 -7.22 |
8.00 | 12.67 |
| ▶ | 22 | 0 5 9 13 |
0.00 272.73 490.91 709.09 |
0.00 +5.86 -7.14 +7.14 |
5.65 | 10.35 |
| ▶ | 24 | 0 5 10 14 |
0.00 250.00 500.00 700.00 |
0.00 -16.87 +1.96 -1.96 |
7.43 | 14.87 |
| ▶ | 27 | 0 6 11 16 |
0.00 266.67 488.89 711.11 |
0.00 -0.20 -9.16 +9.16 |
6.47 | 14.57 |
| ▶ | 31 | 0 7 13 18 |
0.00 270.97 503.23 696.77 |
0.00 +4.10 +5.18 -5.18 |
4.07 | 10.51 |
| ▶ | 36 | 0 8 15 21 |
0.00 266.67 500.00 700.00 |
0.00 -0.20 +1.96 -1.96 |
1.39 | 4.16 |
| ▶ | 41 | 0 9 17 24 |
0.00 263.41 497.56 702.44 |
0.00 -3.46 -0.48 +0.48 |
1.54 | 5.25 |
| ▶ | 46 | 0 10 19 27 |
0.00 260.87 495.65 704.35 |
0.00 -6.00 -2.39 +2.39 |
3.10 | 11.89 |
| ▶ | 53 | 0 12 22 31 |
0.00 271.70 498.11 701.89 |
0.00 +4.83 +0.07 -0.07 |
2.09 | 9.23 |
| ▶ | 58 | 0 13 24 34 |
0.00 268.97 496.55 703.45 |
0.00 +2.09 -1.49 +1.49 |
1.39 | 6.73 |