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* Paul Erlich's standard pentachordal major for Pajara[10] is 4|4(2) #8, or alternatively 6|2(2) b3. | * Paul Erlich's standard pentachordal major for Pajara[10] is 4|4(2) #8, or alternatively 6|2(2) b3. | ||
== | == Things to watch out for == | ||
Requiring the generator to always be | Requiring the generator to always be chroma-positive causes certain issues: | ||
* The major pentatonic scale is a subset of the major scale. The genchain is simply shortened on either end. Thus one would expect the major pentatonic scale contained within Meantone[7] 5|1 to be Meantone[5] 4|0. But instead it's Meantone[5] 0|4. This is because changing the size of the MOS scale often changes the generator to its octave inverse. Meantone[5]'s bright generator is the 4th not the 5th. | * The major pentatonic scale is a subset of the major scale. The genchain is simply shortened on either end. Thus one would expect the major pentatonic scale contained within Meantone[7] 5|1 to be Meantone[5] 4|0. But instead it's Meantone[5] 0|4. This is because changing the size of the MOS scale often changes the generator to its octave inverse. Meantone[5]'s bright generator is the 4th not the 5th. | ||
* It's impossible to determine the | * It's impossible to determine the chroma-positive generator in a non-MOS scale like Meantone[8], thus Meantone[8] 5|2 is ambiguous. | ||
* | * Because the mos type is tuning-dependent, the choice of chroma-positive generator can be tuning-dependent. For example, assume you are using approximately 700¢ for dominant meantone. Then Dominant[12] is 7L 5s (if generator < 700¢), in which case the chroma-positive generator is the fourth, or 5L 7s (if generator > 700¢), meaning that the chroma-positive generator is the fifth. As a result, Dominant[12] 7|4 is ambiguous. | ||
== Other Notations == | == Other Notations == | ||