The electric upright bass (EUB) is an instrument that can perform the musical function of a double bass. It requires only a minimal or 'skeleton' body to produce sound because it uses a pickup and electronic amplifier and loudspeaker. Therefore, a large resonating structure is not required to project the sound into the air. This minimal body greatly reduces the bulk and weight of the instrument. EUBs must always be connected to an amplifier and speaker cabinet to produce an adequate audible sound. The EUB retains enough of the features of the double bass so that double bass players are able to perform on it. Types There are two types: solid-body EUBs and hollowbody EUBs. Solid-body EUBs have no hollow enclosure for the body and, as such, they produce almost no sound without electronic amplification. Solid-body EUBs are connected to an amplifier for practice and live performances. Hollowbody EUBs have a wooden enclosure, which, whilst having a much smaller hollow body cavity than that of a double bass, is still large enough to give the instrument some sound output without amplification, at least for individual practice in a small room. For performing it is connected to an amplifier and speaker. Though the EUB retains some of the tonal characteristics of the double bass, being electronically amplified it produces its own, unique sound. The size and shape of EUB bodies varies. Some EUBs have a very small body, which makes the instrument smaller and lighter in weight. Some EUBs have larger bodies, including the upper bouts, to aid the player in performing higher pitches. Electronics Some EUBs have built-in pickups and volume controls, similar in function to the pickups and knobs on an electric bass (also called the bass guitar). Some EUBs are sold without an onboard pickup or knobs; a player using this instrument would need to purchase a piezoelectric (or magnetic) pickup separately and then attach the pickup to the body or bridge. Playing EUBs sometimes have a long endpin to support the instrument at the appropriate height although some EUBs can be mounted on a stand for playing. As with the double bass, an EUB can be played standing up or sitting on a stool. Usage EUBs are used in a wide range of styles of music, from jazz fusion and jazz to Cuban music and rock music. While four string EUBs are most common, using the same