Thenormal tuning of the 6-stringguitar isE A D G B E(fromthebass stringsto thehigher strings,6->1)
A12-stringguitar, has this tuning:eE-Aa-dD-Gg-BB-EE.in this the lowercase lettersaretunedanoctavehigher. So thelowE,A,DandGstringhave an octave higher tuned string extra,thehighBandEaresimplydouble(same string, same tuning).Because of the hightensionon theneck the twelve-stringguitaris sometimestuned down by a half note or even more.
The tuning;E A D Gfrom lowtohigh. A five-stringbass has an extra string; lowB. the six-string has an extraC string (high).