The twelve-string bass is an electric bass

Electric Bass

Electric bass can mean:*Electric upright bass, the electric version of a double bass*Electric bass guitar*Bass synthesizer*Big Mouth Billy Bass, a battery-powered singing fish...

 with four courses

Course (music)

A course is a pair or more of adjacent strings tuned to unison or an octave and usually played together as if a single string. It may also refer to a single string normally played on its own on an instrument with other multi-string courses, for example the bass string on a nine string baroque...

 each of three 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.

Notable 12-string Bassists

• Tom Petersson
  Tom Petersson
  Tom Petersson is an American musician, best known as the bassist and sometime guitarist for the rock band Cheap Trick.-Career:...
  
   of Cheap Trick
  Cheap Trick
  Cheap Trick is an American rock band from Rockford, Illinois, formed in 1973. The band consists of members Robin Zander , Rick Nielsen , Tom Petersson , and Bun E...
  
  . Tom Petersson is credited with the invention of the 12 string bass.
• Jeff Ament
  Jeff Ament
  Jeffrey Allen Ament is an American musician who serves as the bassist for the American rock band Pearl Jam. Along with Stone Gossard, Mike McCready, and Eddie Vedder, he is one of the founding members of Pearl Jam...
  
   of Pearl Jam
  Pearl Jam
  Pearl Jam is an American rock band that formed in Seattle, Washington, in 1990. Since its inception, the band's line-up has included Eddie Vedder , Jeff Ament , Stone Gossard , and Mike McCready...
  
  . His 12-string bass playing can be heard in the intro to their hit song "Jeremy
  Jeremy (song)
  "Jeremy" is a song by the American grunge band Pearl Jam that features lyrics written by vocalist Eddie Vedder and music written by bassist Jeff Ament. "Jeremy" was released in 1992 as the third single from Pearl Jam's debut album, Ten . The song reached the number five spot on both the Mainstream...
  
  ".
• Doug Pinnick
  Doug Pinnick
  Doug Pinnick sometimes stylised as dUg Pinnick or simply dUg is an American musician best known as the bass guitarist, songwriter, and co-lead vocalist for the hard rock/progressive metal band King's X. He has fourteen albums with King's X, four solo albums, and numerous side projects and guest...
  
   of King's X
  King's X
  King's X is an American hard rock band that combines progressive metal, funk and soul with vocal arrangements influenced by gospel, blues, and British Invasion rock groups. The band's lyrics are largely based on the members' struggles with religion and self-acceptance...
  
  
• Chip Z'nuff of Enuff Z'nuff
  Enuff Z'nuff
  Enuff Z'Nuff, pronounced "enough's enough," is an American glam rock band from Blue Island, Illinois. Founded by singer Donnie Vie and bassist Chip Z'Nuff, this Chicago area band is best known for their charting singles "Fly High Michelle" and "New Thing." Enuff Z'Nuff has continually recorded and...
  
  

Manufacturers of 12-string basses

• Hamer Guitars
  Hamer Guitars
  Hamer Guitars is an American manufacturer of electric guitars. Founded in 1973 by vintage guitar shop owners, Jol Dantzig and his business partner Paul Hamer. Early instruments featured guitar designs based on the Gibson Explorer and Flying V...
  
  
• Dean Guitars
  Dean Guitars
  Dean Guitars is an American manufacturer of guitars. It was founded in 1976 by Dean Zelinsky in Chicago, Illinois and is currently under the ownership of Armadillo Enterprises in Tampa, Florida.- History :...
  
  
• Chandler Guitars
• MusicVox Guitars
• Waterstone Guitars

Other Bass Guitars with Twelve Strings

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.

Six-course Bass

A bass with six courses each of two strings was played by John Paul Jones

John Paul Jones (musician)

John Paul Jones is an English multi-instrumentalist, songwriter, composer, arranger and record producer. Best known as the bassist, mandolinist, and keyboardist for English rock band Led Zeppelin, Jones has since developed a solo career and has gained even more respect as both a musician and a...

 of Led Zeppelin

Led Zeppelin

Led Zeppelin were an English rock band, active in the late 1960s and throughout the 1970s. Formed in 1968, they consisted of guitarist Jimmy Page, singer Robert Plant, bassist/keyboardist John Paul Jones, and drummer John Bonham...

. This instrument was made by Hugh Manson.

Twelve-course Bass

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.

Six-course bass

• John Paul Jones bass guitars