Wednesday, February 25, 2009
Scale of the Day: D Pythagorean Chromatic - Ionian Mode
The D Pythagorean Chromatic - Ionian Mode - Scale. The 4/3 perfect fourth is the only utonal member of this scale (in this example, Ionian means having just one utonal member). All the other frequency ratios have the largest prime factor (3, Pythagorean tunings are 3-limit) in the numerator. This necessitates the unusual spelling of these intervals. The 2187/2048 is the Pythagorean augmented unison represented as D-sharp. The 19683/16384 is the Pythagorean augmented second represented as E-sharp. Pythagorean scales do not have enharmonic equivalence the way equal temperament does.