Eight-string bass guitar

An eight-string bass guitar is a type of bass guitar with double course strings normally tuned in octaves, with both strings in a course usually played simultaneously. As on a 12-string guitar, this produces a natural chorus effect due to the subtle differences in string timbre. Such approach has been extended with the introduction of 10-, 12-, 15- or more-string bass guitars, which either double the strings of standard 5- or 6-string basses or even triple the strings of normal 4-, 5- or 6-string basses.

The 8-string bass guitar was invented by electrical engineer, bass player and musician, Eric Krackow, who had played with Al Kooper's early band, The Aristo-Cats, in the late 1950s and early 1960s. It bothered Eric that 50% of the quartet would be tied up with the guitar doubling the bass line while playing tunes like Jimi Hendrix's "Manic Depression." Eric, finding it too awkward to play the unison octaves himself on complex songs, remembered the 12-string guitar principle and made a prototype 8-string bass from a modified four string bass. In 1967, Eric and a business partner (Steve Wittels) brought it to Sid Hack of Univox Corp. on Long Island, which company was the importer for Hagström guitars. Sid liked the idea and ordered a trial run of 500 units. The success of that test run resulted in further production and sales.

The first 8-string bass guitars were made by Hagström, from 1967 to 1969 with a total of 2,249 being manufactured. An 8-string bass guitar is strung with paired, octaved strings, similar to those of a regular 12-string guitar. Standard tuning is usually as so:

Chris Squire of Yes often tuned his Raney 8-string bass eE-aA-aD-dG, so that notes played on the upper two courses sound as open fifths.

8-string basses are usually fretted; however, fretless 8-string basses have been known to exist, though would usually be a custom make. Though once rare, many well-known guitar manufacturers now make 8-string basses commercially available, such as Dean Guitars, ESP Guitars, Hamer Guitars, Schecter Guitars, Washburn Guitars, Rickenbacker and Hagström among others. Warmoth Guitars also offers an 8-string conversion neck that allows a normal 4-string, 34" scale bass to be converted to 8 strings.

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Wikipedia