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.
Appalachian dulcimer half," "6½" or "6+" fret a half step below the octave. This enables one to play in the Ionian mode when tuned to D3-A3-D4 (the traditional tuning for the Mixolydian mode), where the scale starts on the open (unfretted) string. This arrangement is often found to be more conducive to chord-melody play. It also became common to add a fret one octave up from the 6+ fret, called the "13+" fret, and by the late 1970s these additional frets had become standard. Eventually, some builders began to offer further additional frets at the "1+" and "8+" positions or (as an