Capo plays a B note for any capo position at or below the seventh fret), and thus a performer does not need to adjust for or relearn the entire fretboard as they might with retuning. The scale length of the strings of an instrument affects the timbre of the strings, and thus the use of a capo may alter the tone of the instrument. Musicians also use capos to bring a guitar tuned below standard up to standard tuning. Manufacturers sometimes recommend tuning a twelve-string guitar a whole-step or more below standard to offset the additional stress of the additional strings.
Twelve-string guitar downward strum is the higher-octave string; however, Rickenbacker usually reverses this arrangement on its electric 12-string guitars. The tuning of the second string in the third course (G) varies: some players use a unison string, while others prefer the distinctive high-pitched, bell-like quality an octave string makes in this position. Another common variant is to tune the octave string in the sixth (lowest) course "two" octaves above the lower string, rather than one. Some players, either in search of distinctive tone or for ease of playing, remove some doubled strings. For example, removing the higher octave from the three bass