2edt: Difference between revisions
Created page with "'''2EDT''', if the attempt is made to use it as an actual scale, would divide the tritave into two equal parts, each of size 950.9775 cents, which is to say sqrt(3) as..." Tags: Mobile edit Mobile web edit |
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== | == Theory == | ||
[[ | As a temperament in the [[3.5 subgroup]], it tempers out [[27/25]], equating 5/3 with 9/5. Because of this, it is related to the [[bug]] temperament. In fact, removing octaves from the [[bug]] temperament results in a 3.5 interpretation of 2edt. | ||
Since [[26/15]] is a [[convergent]] of sqrt(3), 26/15 (and its [[tritave complement]] 45/26) are good rational representations of the square root of 3. 2edt thus tempers out (26/15)<sup>2</sup> / (3/1) = [[676/675]], the island comma. | |||
[[ | === Harmonics === | ||
[[ | {{Harmonics in equal|2|3|1|columns = 14}} | ||
== Relationship to octave temperaments == | |||
One step of 2edt can represent the generator for any rank-2 octavated temperament which takes 2 generators to reach the 3rd harmonic, such as [[semaphore]] and [[monzismic]]. | |||
Latest revision as of 04:54, 19 September 2026
| ← 1edt | 2edt | 3edt → |
(convergent)
2 equal divisions of the tritave, perfect twelfth, or 3rd harmonic (abbreviated 2edt or 2ed3), is a nonoctave tuning system that divides the interval of 3/1 into 2 equal parts of about 951 ¢ each. Each step represents a frequency ratio of 31/2, or the square root of 3.
Theory
As a temperament in the 3.5 subgroup, it tempers out 27/25, equating 5/3 with 9/5. Because of this, it is related to the bug temperament. In fact, removing octaves from the bug temperament results in a 3.5 interpretation of 2edt.
Since 26/15 is a convergent of sqrt(3), 26/15 (and its tritave complement 45/26) are good rational representations of the square root of 3. 2edt thus tempers out (26/15)2 / (3/1) = 676/675, the island comma.
Harmonics
| Harmonic | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Error | Absolute (¢) | -249 | +0 | +453 | +67 | -249 | +435 | +204 | +0 | -182 | -347 | +453 | +314 | +186 | +67 |
| Relative (%) | -26.2 | +0.0 | +47.6 | +7.0 | -26.2 | +45.8 | +21.4 | +0.0 | -19.2 | -36.5 | +47.6 | +33.1 | +19.6 | +7.0 | |
| Steps (reduced) |
1 (1) |
2 (0) |
3 (1) |
3 (1) |
3 (1) |
4 (0) |
4 (0) |
4 (0) |
4 (0) |
4 (0) |
5 (1) |
5 (1) |
5 (1) |
5 (1) | |
Relationship to octave temperaments
One step of 2edt can represent the generator for any rank-2 octavated temperament which takes 2 generators to reach the 3rd harmonic, such as semaphore and monzismic.