The saxophone (also referred to informally as the sax) is a conical-bore woodwind musical instrument. Saxophones are usually made of brass and played with a single-reed mouthpiece similar to that of the clarinet. The saxophone was invented by the Belgian instrument maker Adolphe Sax in 1846. He wanted to create an instrument that would be the most powerful and vocal of the woodwinds, and the most adaptive of the brass—that would fill the vacant middle ground between the two sections. He patented the saxophone on June 24, 1846 in two groups of seven instruments each. Each series consisted of instruments of various sizes in alternating transposition. The series pitched in B♭ and E♭, designed for military bands, has proved extremely popular and most saxophones encountered today are from this series. Instruments from the so-called "orchestral" series pitched in C and F never gained a foothold, and the B♭ and E♭ instruments have now replaced the C and F instruments in classical music.
While proving very popular in military band music, the saxophone is most commonly associated with jazz and classical music. There is substantial repertoire of concert music in the classical idiom for the members of the saxophone family. Saxophone players are called saxophonists.
The tenor saxophone is a medium-sized member of the saxophone family, a group of instruments invented by Adolphe Sax in the 1840s. The tenor, with the alto, are the two most common types of saxophones. The tenor is pitched in the key of B Flat♭, and written as a transposing instrument in the treble clef, sounding an octave and a major second lower than the written pitch. Modern tenor saxophones which have a high F# key have a range from A♭2 to E5 (concert) and are therefore pitched one octave below the soprano saxophone. People who play the tenor saxophone are known as "tenor saxophonists" or "tenor sax players".
The tenor saxophone uses a larger mouthpiece, reed, and ligature than the alto and soprano saxophones. Visually, it is easily distinguished from these instruments by the bend in its neck, or its crook, near the mouthpiece.
The tenor saxophone is used in many different types of ensembles, including concert bands, big band jazz ensembles, small jazz ensembles, and marching bands. It is occasionally included in pieces written for symphony orchestra and for chamber ensembles; three examples of this are Ravel's Boléro, Prokofiev's suite from Lieutenant Kijé,and Webern's Quartet for violin, clarinet, tenor saxophone, and piano. In concert bands, the tenor plays mostly a supporting role, sometimes sharing parts with the euphonium, horn and trombone. In jazz ensembles, the tenor plays a more prominent role, often sharing parts or harmonies with the alto saxophone.