Canopus
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For technical information see No-twos subgroup temperaments#Canopus
Canopus is the rank two 3.5.7 subgroup temperament tempering out 16875/16807, the amount by which 27/7 exceeds four 7/5s. Having a generator of ~7:5, it possesses non-trivial MOS of the families 1L 2s, 3L 1s, 3L 4s, 3L 7s, and (in most cases) 10L 3s. As 16875/16807 = (540/539)2*(3025/3024), Canopus can be extended to the 3.5.7.11/4 subgroup extremely naturally by tempering out these two commas; prime 53 can additionally be incorporated by means of tempering out 1325/1323, equating (7/5)2 = 49/25 to 53/27.
Interval table
In the below, tritave-reduced harmonics and subharmonics are indicated in bold.
| # | Cents* | Approximate Ratios |
|---|---|---|
| 3.5.7.11/4.53 subgroup | ||
| −3 | 149.9 | 12/11, 49/45 |
| −2 | 733.9 | 55/36, 75/49, 81/53, 84/55 |
| −1 | 1318.0 | 15/7 |
| 0 | 0.0 | 1/1 |
| 1 | 584.0 | 7/5 |
| 2 | 1168.0 | 49/25, 53/27, 55/28, 108/55 |
| 3 | 1752.0 | 11/4, 135/49 |
| 4 | 434.1 | 9/7 |
| 5 | 1018.1 | 9/5 |
| 6 | 1602.1 | 53/21, 63/25 |
| 7 | 284.1 | 33/28, 53/45 |
| 8 | 868.1 | 33/20, 81/49 |
| 9 | 1452.1 | 81/35 |
| 10 | 134.2 | 27/25, 53/49 |
* In 3.5.7-targeted DKW tuning
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Todo: add interval table, tuning spectrum, etc. |