Twelve-string bass

The twelve-string bass is an electric bass with three courses on each of four strings.

Normal tuning is eeE-aaA-ddD-ggG, with one string of each course tuned similarly to the corresponding string of the four-string bass, and the remaining two strings tuned to the octave.

The first known 12 string bass guitar, the "Hamer Quad," was designed by Jol Dantzig and built in 1977 for Tom Petersson by Hamer Guitars. Petersson's Cheap Trick bandmate Rick Nielsen reports that Petersson first conceived of the instrument in 1973, and worked with Hamer over the next few years refining the design.

Although the model most commonly known as "the 12-string bass" is as described above, several other bass guitars with a total of twelve strings have been built to rarer or unique specifications.

A bass with six courses each of two strings was played by John Paul Jones of Led Zeppelin. This instrument was made by Hugh Manson.

Basses have been built with twelve single-string courses, and various tunings. These are not normally played as a conventional bass guitar, but rather both hands are used on the fretboard.

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