This tuning 5-4-3M-4-5 is called so because the part 5-4 is the tuning of a 3-string bouzouki and the part 5-4-3M is the Swedish troll violin tuning , while the part 4-3M-4-5 is the tuning of a charango. It is an open tuning.
E.g. FOR C MAJOR
C2-G2-C3-E3-A3-E4
OR
C3-G3-C4-E4-A4-E5
One of the great advantages of this tuning is that
a) The ukulele part of the tuning 4-3M-4 allows for standard guitar playing of chords
b) The Swedisg troll part of the tuning 5-4-3M allows for accomanying with a power root chord 5-4 , complicated soloing on the 2nd (from higher) string that normally would require many major or minor chords for accomanying.
Thus this tuning combines techniques of the ancient 1st generation music with the techniques of the 2nd generation classical period of music.
