Contrabass trombone

The contrabass trombone (German: Kontrabassposaune, Italian: trombone contrabbasso) is the lowest-pitched instrument in the trombone family of brass instruments. While modern instruments are pitched in 12′ F with a single slide, the first practical contrabass trombones appeared in the mid-19th century built in 18′ B♭ an octave below the tenor trombone with a double slide. German opera composer Richard Wagner notably called for this instrument in his Der Ring des Nibelungen opera cycle in the 1870s, and contrabass trombone has since appeared occasionally in large orchestral works without becoming a permanent member of the modern orchestra.

Since the late 20th century, the double-slide contrabass has largely been supplanted by the less cumbersome bass-contrabass in F, a fourth below the B♭ tenor and bass trombones. In the 21st century the contrabass has enjoyed something of a revival, particularly in film and video game soundtracks.