Alternate bass

In music, alternate bass is a performance technique on many instruments where the bass alternates between two notes, most often the root and the fifth of a triad or chord.

The perfect fifth is often, but not always, played below the root, transposed down an octave creating a fourth interval.

The alternation between the root note and the fifth scale degree below it creates the characteristic sound of the alternate bass.

In the following example in the C major chord C is located on the fifth string while G is located on the adjacent sixth (lowest) string and in the F major chord F is located on the adjacent fourth string: Alternate bass lines are also used on the double bass in country music, bluegrass music and related genres.

On the Stradella bass system commonly found on accordions, the left-hand bass-note buttons are arranged according to the circle of fifths.