B tuning

B Tuning or B Standard Tuning is the standard tuning for a seven string guitar, where the strings are tuned B-E-A-D-G-B-E. B tuning can also be achieved on a six-string guitar, when the strings are tuned B-E-A-D-F♯-B, known then as Baritone Tuning.

This tuning is popular among several different types of metal bands.

Some bands use a tuning known as "drop A tuning", where they drop the low B to A, so the tuning for a 7-string guitar is as follows A1-E2-A2-D3-G3-B3-E4.

Also, for a 6-string guitar, drop A tuning is achieved by tuning all strings down a 4th with the lowest string tuned 1 additional step down as follows A1-E2-A2-D3-F#3-B3.

This is a "drop 1" tuning in the key of B (i.e. tune the whole guitar down a perfect fourth from standard tuning, then tune the 6th string a whole step down).