This tuning combines 3 strings that are in major or minor triad and a 5 away 3 strings that are again a 5th apart (e.g. mandocello) Or it can be in the reverse order first the 5ths then the major or minor triad. In this way both types of playing the ancient that can accompany a melody only with an interval of 5th or the modern that requires accompanying with triad major or minor chords can be played.
E.g.
C2-E2-G3-D3-A3-E4 3M-3m-5-5-5
F2-A2-C3-G4-D4-A4 3M-3m-5-5-5
or
F2-C2-G3-D3-F4-A4 5-5-5-3m-3M
or
C2-G2-D3-A3-C4-E4 5-5-5-3m-3M
or
F2-C2-G3-D3-F#4-A4 5-5-5-3M-3m
or
Eb2-Bb2-F3-C4-E4-G4 5-5-5-3M-3m
