The bass is a member of the rhythm section. This term comes from an earlier period in popular music when swing orchestras dominated the scene and dance bands consisted of a rhythm section, a brass section, and a woodwind section. These days, most pop groups consist only of a rhythm section plus a singer(s). Nonetheless, the term rhythm section is still in use.

A rhythm section is composed of bass, drums, piano, and guitar. You do not need all four instruments to create a rhythm section. In other words, some rhythm sections consist only of a bass and a piano or a bass and a drum set. Whatever the combination, the rhythm section is responsible for the rhythmical and the harmonic underpinning of the music. In short, the rhythm section backs up or accompanies singers and soloists. The role of the bass in the rhythm section is twofold:

• To define and maintain the pulse and groove of the music

• To highlight the root of each chord

As you learned in Chapter 5, a root is the letter name of each chord. For example, the root of a C-major triad is a C. A good bass player knows how important it is to create bass lines that stress the roots even when playing intricate lines. Do you have to play every root? No. There is some wiggle room. However, you must be judicious and frugal when sidestepping the root. You should avoid roots only when a bass line or lick is compelling enough to temporarily sway the ear in another direction. Also, bass players sometimes experiment with alternate roots, adding extra harmonic sparkle to the chord changes.

For all intents and purposes, piano and guitar share the same responsibility in the rhythm section. They are the chordal instruments. When they play with a bass player, these instruments don't always plays roots, so, again, it's important for the bassist to play roots. If the bass doesn't, the music will lose its anchor and drift into a state of ambiguity, even confusion.

The drummer is the timekeeper. Together with the bass, the drums hold down the fort. The bass and drums work together to ensure steadiness and forward momentum in the music. In rock and pop, the bass and the bass drum (sometimes called kick drum) even play in tandem most of the time. Bass players and drummers share a special symbiotic relationship.