The alto saxophone is a variety of the saxophone, a family of woodwind instruments invented by Adolphe Sax. The alto is the third smallest of the saxophone family, which consists of ten sizes of saxophone. The alto is the second most common size of saxophone, and is also the size most commonly included in classical compositions. In concert band, the alto typically plays the counter-melody in a supporting role, but it sometimes gets the melody. It often shares parts with the clarinet, horn, and trumpet.
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