Bass line

A bassline (also known as a bass line or bass part) is the term used in many styles of popular music, such as jazz, blues, funk, dub and electronic, or traditional music, for the low-pitched instrumental part or line played by a rhythm section instrument such as the electric bass, double bass, cello, tuba or keyboard (piano, Hammond organ, electric organ, or synthesizer). It is also used sometimes in classical music. In solo performance, basslines may simply be played in the lower register of any instrument such as guitar while melody and/or further accompaniment is provided in the middle or upper register. In solo music for piano and pipe organ, these instruments can be used to play a deep bassline.

Basslines in popular music often use "riffs" or "grooves", which are usually simple, appealing musical motifs or phrases that are repeated, with variation, throughout the song. "The bass differs from other voices because of the particular role it plays in supporting and defining harmonic motion. It does so at levels ranging from immediate, chord-by-chord events to the larger harmonic organization of a [sic] entire work." Bassline riffs usually emphasize the chord tones of each chord (usually the root note, the third note, or the fifth note), which helps to define a song's key. At the same time, basslines work along with the drum part and the other rhythm instruments to create a clear rhythmic pulse.

The type of rhythmic pulse used in basslines varies widely in different types of music. In swing jazz and jump blues, basslines are often created from a continuous sequence of quarter notes in a mostly scalar, stepwise part called a "walking bass line". In Latin, salsa music, jazz fusion, reggae, electronica, and some types of rock and metal, basslines may be very rhythmically complex and syncopated. In bluegrass and traditional country music, basslines often emphasize the root and fifth of each chord.

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