Tonal Plexus V7 Tritones in Just Intonation

Описание: Dominant 7th chords contain a diminished 5th between the 3rd and 7th, often called a tritone, although tritones are, strictly speaking, always augmented 4ths, not diminished 5ths (tritone = 3 tones = 3 whole tones in a row e.g. C to D to E to F# = C : F# = augmented 4th). The misnomer is indicative of the way pitches are named enharmonically in 12ET, where for example F# and Gb are the same pitch. In 12ET, two dominant chords can share the same pitches between their 3rds and 7ths, swapping roles of those pitches between the chords, because an augmented 4th and a diminished 5th use the same exact pitches. This cant happen in Just Intonation. In Just Intonation, a diminished 5th will never be an augmented 4th. This video shows how in JI either the 3rd or 7th can be used as a common tone, but not both. One or the other common tones can be kept in a dominant 7th chord whose root is either an augmented fourth or a diminished fifth away, since those intervals are not the same in Just Intonation. Make sense?

Note: the captions in this video introduced blips into the audio for some reason and I couldnt fix it; sorry about that!

Find out more about the Tonal Plexus at [ new website as of 2015 — http://hpi.zentral.zone ] and see the blog at [ http://hpi.zentral.zone/blog ] for a post with more information than is given here.