Just intonation point: Difference between revisions
No edit summary |
No edit summary |
||
Line 1: | Line 1: | ||
'''JIP''' ('''just intonation point'''), or commonly denoted "J", is a point in ''p''-limit [[Vals and tuning space|tuning space]] which represents untempered ''p''-limit JI. Specifically, it is equal to {{val|log<sub>2</sub>2 log<sub>2</sub>3 log<sub>2</sub>5 … log<sub>2</sub>''p''}}, meaning that each prime ''q'' in the ''p'' | '''JIP''' ('''just intonation point'''), or commonly denoted "J", is a point in ''p''-limit [[Vals and tuning space|tuning space]] which represents untempered ''p''-limit JI. Specifically, it is equal to {{val|log<sub>2</sub>2 log<sub>2</sub>3 log<sub>2</sub>5 … log<sub>2</sub>''p''}}, meaning that each prime ''q'' in the ''p''-prime limit is tempered to log<sub>2</sub>''q'' octaves (which is exactly the just value of the prime ''q''). If M is a monzo, then <J|M> is M evaluated in terms of octaves. If we shift to weighted coordinates, so that M = {{monzo|''m''<sub>2</sub> ''m''<sub>3</sub> ''m''<sub>5</sub> … ''m''<sub>''p''</sub>}} is represented by the ket vector {{monzo|e<sub>2</sub>log<sub>2</sub>2 e<sub>3</sub>log<sub>2</sub>3 e<sub>5</sub>log<sub>2</sub>5 … e<sub>''p''</sub>log<sub>2</sub>''p''}}, then J becomes correspondingly the bra vector {{val|1 1 1 … 1}}. | ||
As seen in the 5-limit [[projective tuning space]] diagram, it is the red hexagram in the center. | As seen in the 5-limit [[projective tuning space]] diagram, it is the red hexagram in the center. |