bass

The bass guitar (or simply bass) is a plucked string instrument similar in appearance and construction to an electric or an acoustic guitar, except with a longer neck and scale length, and typically four to six strings or courses.
The four-string bass is usually tuned the same as the double bass, which corresponds to pitches one octave lower than the four lowest-pitched strings of a guitar (E, A, D, and G). It is played primarily with the fingers or thumb, or striking with a pick. The electric bass guitar has pickups and must be connected to an amplifier and speaker to be loud enough to compete with other instruments.
Since the 1960s, the bass guitar has largely replaced the double bass in popular music as the bass instrument in the rhythm section. While types of basslines vary widely from one style of music to another, the bassist usually plays a similar role: anchoring the harmonic framework and establishing the beat. Many styles of music include the bass guitar, and it is occasionally a soloing instrument.

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