A selection of bass effect pedals at a music store.
Main article: Bass effects
Bass effects are electronic effects units that are designed for use with the low pitches created by an electric bass or for an upright bass used with a bass amp or PA system. Two examples of bass effects are fuzz bass and bass chorus. Some bass amplifiers have built-in effects, such as overdrive or chorus. Upright bassists in jazz, folk, blues and similar genres may use a bass preamplifier, a small electronic device that matches the impedance between the piezoelectric pickup and the amp or PA system. Bass preamps also allow for the gain of the signal to be boosted or cut. Some models also offer equalization controls, a compressor, and a DI box connection.