The next two scales are made entirely from intervals of 7 semitones , in other words intervals of 5 and intervals of 3 or their complementary intervals of 6ths . They come from successive triad major or minor chords of 2 or 3 frets in the uniform tuning by 5ths of string instruments. In addition these scales , when reduced to a single octave they give the diatonic scale.
1) C2-G2-E3-B3-G4-D5-A6-F6-C8 6 OCTAVES
INTERVALS IN SEMITONES
7-9-7-8-7-7-8-7
2) C2-G2-B2-F3-A3-E4-G4-D5 3 OCTAVES
INTERVALS IN SEMITONES
7-4-7-4-7-3-7
Such scales can be used also for tuning of strings so as to give major minor triads with few only frets (2,3 frets)