The tuba is the largest and lowest-pitched brass instrument. Sound is produced by vibrating or "buzzing" the lips into a large cupped mouthpiece. It is one of the most recent additions to the modern symphony orchestra, first appearing in the mid-19th century, when it largely replaced the ophicleide. Tuba is Latin for trumpet or horn. The horn referred to would most likely resemble what is known as a baroque trumpet.
An orchestra usually has a single tuba, though an additional tuba may be asked for. It is the principal bass instrument in symphonic and military bands, and those ensembles generally have more. It serves as the bass of the brass section and of brass quintets and choirs, as well as reinforcement for the bass voices of the strings and woodwinds, and as a solo instrument.
When used in modern jazz, tubas usually fill the traditional bass role, although it is not uncommon for them to take solos. New Orleans style Brass Bands like Dirty Dozen Brass Band, Rebirth Brass Band, and Nightcrawlers Brass Band feature a sousaphone as the bass instrument. Miles Davis made use of a tuba, played by Bill Barber, in his album Birth of the Cool, released in June, 1950. One of the most prominent tubists specializing in jazz is the New York City-based Marcus Rojas, who has performed frequently with bandleader Henry Threadgill. Another notable group is the Modern Jazz Tuba Project, founded by R. Winston Morris, which consists entirely of tubas and euphoniums with rhythm section. The tuba has also played a large role in ragtime music and in big band music.