Rank-3 scale: Difference between revisions

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|Can tessellate the entire lattice of pitch classes that it lives in
|Can tessellate the entire lattice of pitch classes that it lives in
|Scale pattern products = rank-3 Fokker blocks (superset of Pairwise DE/MOS scales)
|MOS pattern products = rank-3 Fokker blocks (superset of Pairwise DE/MOS scales)
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|[[Recursive structure of MOS scales|Recursive structure]], Uniquely defined by step signature and mapping (implies mirror-symmetric)
|[[Recursive structure of MOS scales|Recursive structure]], Uniquely defined by step signature and mapping (implies mirror-symmetric)
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Two MOS scales can be combined into a rank-3 scale as a ''[[product word|scale pattern product]]'', which reduces back to the two MOS scales when two of the three pairs of interval sizes are equated.
Two MOS scales can be combined into a rank-3 scale as a ''[[product word|scale pattern product]]'', which reduces back to the two MOS scales when two of the three pairs of interval sizes are equated.


When associated with a mapping, product words are the rank-3 ''[[Fokker blocks]]''. Fokker blocks have ''unison vectors'', which generalize the concept of the chroma of MOS scales to higher ranks. If these intervals are plotted onto a plane representing rank-3 octave equivalent pitch space, they tile the space into Fokker blocks which differ by combinations of these unison vectors. Rank-2 Fokker blocks are the MOS scales, so Fokker blocks can be considered a generalization of MOS scales into higher ranks.
When associated with a mapping, MOS pattern products are the rank-3 ''[[Fokker blocks]]''. Fokker blocks have ''unison vectors'', which generalize the concept of the chroma of MOS scales to higher ranks. If these intervals are plotted onto a plane representing rank-3 octave equivalent pitch space, they tile the space into Fokker blocks which differ by combinations of these unison vectors. Rank-2 Fokker blocks are the MOS scales, so Fokker blocks can be considered a generalization of MOS scales into higher ranks.


Product words have maximum variety at most 4. The scale steps can be readily notated, sorted by size, as '''''L''''', '''''l''''', '''''S''''', '''''s''''', and they satisfy '''''L''''' - '''''l''''' = '''''S''''' - '''''s'''''.  
MOS pattern products have maximum variety at most 4. The scale steps can be readily notated, sorted by size, as '''''L''''', '''''l''''', '''''S''''', '''''s''''', and they satisfy '''''L''''' - '''''l''''' = '''''S''''' - '''''s'''''.  


Any Fokker block where the unison vectors are smaller than the smallest steps will be constant structures (CS). Not all Fokker blocks are CS.
Any Fokker block where the unison vectors are smaller than the smallest steps will be constant structures (CS). Not all Fokker blocks are CS.