The standard design for the electric bass has four strings, tuned E, A, D and G, in fourths such that the open highest string, G, is an eleventh (an octave and a fourth) below middle C, making the tuning of all four strings the same as that of the double bass. This tuning is also the same as the standard tuning on the lower four strings on a 6-string guitar, only an octave lower. String types include all-metal strings (roundwound, flatwound, groundwound, or halfwound), metal strings with different coverings, such as tapewound and plastic-coatings. The variety of materials used in the strings gives bass players a range of tonal options.
In the 1950s, bassists often used flatwound strings with a smooth surface, which had a smooth, damped sound reminiscent of a double bass. In the 1960s and 1970s, roundwound bass strings similar to guitar strings became popular. Roundwounds have a brighter timbre with greater sustain than flatwounds. Flatwounds are still used by some bassists who want a more 'vintage' or Motown-style sound.
A number of other tuning options and bass types have been used to extend the range of the instrument. The most common are:
* Four strings with alternate tunings to obtain an extended lower range.
* Five strings usually tuned B-E-A-D-G (the earliest 5 string basses were tuned E-A-D-G-C and this is still a popular tuning for jazz). Other tunings such as C-E-A-D-G are used, but this is rare. The 5th string provides a greater lower or upper range than the 4-string bass, and gives access to more notes for any given hand position.
* Six strings (usually B-E-A-D-G-C, but sometimes E-A-D-G-B-E or F#-B-E-A-D-G). The 6-string bass is a 4-string bass with an additional low "B" string and a high "C" string. While much less common than 4- or 5-string basses, they are still used in Latin, jazz, and several other genres. A few players have tuned the high C down to a B (giving B-E-A-D-G-B) matching the E-A-D-G-B found on the first five strings of an acoustic or electric guitar.
* Detuners, such as the Hipshot, are mechanical devices operated by the right or left-hand thumb that allow one or more strings to be quickly detuned to a pre-set lower pitch. Hipshots are typically used to drop the "E"-string down to "D" on a four string bass.
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