Skip fretting system 53 3 17: Difference between revisions

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This layout allows someone to play in 53-edo on a 17.666-edo guitar, by tuning the guitar in major thirds -- that is, with 17\53 between each pair of adjacent strings. It offers a big range -- very slightly wider than the [[Kite Guitar]]'s -- and a playable layout, with strikingly easy 5-limit chords.   
This layout allows someone to play in 53-edo on a 17.666-edo guitar, by tuning the guitar in major thirds -- that is, with 17\53 between each pair of adjacent strings. It offers a big range -- very slightly wider than the [[Kite Guitar]]'s -- and a playable layout, with strikingly easy 5-limit chords.   


An important drawback is that harmonics 3 and 7 lie on the same string, making a harmonic 7:6 difficult to play. (Doing so requires reaching across three strings and down 13 frets.) The octave-complement of 7/6, 12/7, is similarly difficult.
An important drawback is that, because harmonics 3 and 7 lie on the same string, a harmonic 7:6 is difficult to play. (Doing so requires reaching back 13 frets, or 883 cents, as well as across three strings.) Perhaps counter-intuitively, 12:7, the octave-complement of 7:6, is much easier to play, requiring a stretch of only 9 frets or 611 cents.


The diagram below, which could be interpreted 20 frets of a 12-string guitar, shows where each of the 15-limit harmonics lies. Since 53-edo is mostly (see below) for the exception consistent in the 15-limit, these harmonics' positions imply where every interval in that group lies. (For instance, to play 7/6 you move up one string and down one fret, because that takes you from harmonic 3 to harmonic 7.) Octaves are indicated as powers of 2 (specifically 1, 2, 4 and 8).
The diagram below, which could be interpreted 20 frets of a 12-string guitar, shows where each of the 15-limit harmonics lies. Since 53-edo is mostly (see below) for the exception consistent in the 15-limit, these harmonics' positions imply where every interval in that group lies. (For instance, to play 7/6 you move up one string and down one fret, because that takes you from harmonic 3 to harmonic 7.) Octaves are indicated as powers of 2 (specifically 1, 2, 4 and 8).


The exception to the above consistency rule of thumb is the ratios 11/7 (and its octave-complement 14/11). Since 11:8 is 7.9 cents flat and 7:4 is 4.8 cents sharp in 53-edo, the distance between them is 7.9 + 4.8 = 12.7 cents too wide. 12.7 cents is more than half of 53-edo's step size of 22.6 cents. Thus whereas the diagram below suggests that 11:7 is 34 steps wide, in fact 53-edo's best approximation to 11:7 is 35 steps wide. But that best approximation is still 10 cents sharp, so both approximations are roughly equally wrong, just in opposite directions.
The exception to the above consistency rule of thumb is the ratios 11/7 (and its octave-complement 14/11). Since 11:8 is 7.9 cents flat and 7:4 is 4.8 cents sharp in 53-edo, the distance between them is 7.9 + 4.8 = 12.7 cents too wide. 12.7 cents is more than half of 53-edo's step size of 22.6 cents. Thus whereas the diagram below suggests that 11:7 is 34 steps wide, in fact 53-edo's best approximation to 11:7 is 35 steps wide. But that best approximation is still 10 cents sharp, so both approximations are roughly equally wrong, just in opposite directions.
     20 frets of a hypothetical 12-string guitar tuned this way:
     20 frets of a hypothetical 12-string guitar tuned this way: