All fifths tuning
Among guitar tunings, all-fifths tuning refers to the set of tunings in which each interval between consecutive open strings is a perfect fifth. All-fifths tuning is also called fifths, perfect fifths, or mandoguitar. The conventional "standard tuning" consists of perfect fourths and a single major third between the g and b strings: E-A-d-g-b-e' All-fifths tuning has the set of open strings C-G-d-a-e'-b' or G'-D-A-e-b-f♯', which have intervals of 3 octaves minus a half-step between the lowest and highest string. The conventional tuning has an interval of 2 octaves between lowest and highest string. All-fifths tuning is a tuning in intervals of perfect fifths like that of a mandolin or a violin. It has a wide range. It was used by jazz guitarist Carl Kress in the form B♭'-F-c-g-d'-a'. (Wikipedia).
