SN scale: Difference between revisions
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Each iteration of a) increasing the rank of the scale by 1. | Each iteration of a) increasing the rank of the scale by 1. | ||
An SN scale of rank 2, a 2-SN scale, is a [[MOS scale]]. Accordingly, SN scales are a generalization of MOS scales into arbitrary rank. | An SN scale of rank 2, a 2-SN scale, is a [[MOS scale]]. Accordingly, SN scales are a generalization of MOS scales into arbitrary rank. ETs can be considered to be 1-SN scales, which can be generated by applying a) once, introducing a step of a single degree of the ET. | ||
SN scales are inversionally symmetric / invariant under reversal, and may be uniquely defined by a ''step signature'' - a generalisation of the MOS signature into arbitrary rank. | SN scales are inversionally symmetric / invariant under reversal, and may be uniquely defined by a ''step signature'' - a generalisation of the MOS signature into arbitrary rank. | ||
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The double harmonic scale can be generated by iterating a) three times, introducing first the octave, then the fifth, then the major third, leading to a major seven tetrad, and then applying b) once. It has step signature 2L 1M 4s, and in the symmetric mode, it has step arrangement sLsMsLs. | The double harmonic scale can be generated by iterating a) three times, introducing first the octave, then the fifth, then the major third, leading to a major seven tetrad, and then applying b) once. It has step signature 2L 1M 4s, and in the symmetric mode, it has step arrangement sLsMsLs. | ||
These scales all have a period of an octave - and therefore a) first introduces the interval of an octave | These scales all have a period of an octave - and therefore a) first introduces the interval of an octave, however, the period of a SN scale, and the mapping of any new smallest step introduced, is arbitrary. | ||
SN scales are a subset of [[MOS Cradle Scales]]. | SN scales are a subset of [[MOS Cradle Scales]]. | ||
SN scales are based on epi-Christoffel words form combinatorics, which generalize finite Sturmian words, which are equivalent to well-formed scales, and equivalently equivalent to MOS scales that are not ''Multi-MOS'' scales, MOS scales of more than one period, typically with a period that divides the octave evenly. | SN scales are based on epi-Christoffel words form combinatorics, which generalize finite Sturmian words, which are equivalent to well-formed scales, and equivalently equivalent to MOS scales that are not ''Multi-MOS'' scales, MOS scales of more than one period, typically with a period that divides the octave evenly. | ||