quality:corruption
Contrabass trombone

The contrabass trombone is the lowest trombone, first appearing in BB♭ an octave below the tenor with a double slide. This design was commissioned by Wagner in the 1870s for his Der Ring des Nibelungen opera cycle. Since the late 20th century however, it has largely been supplanted by a less cumbersome single-slide bass-contrabass instrument pitched in 12' F. With two valve attachments to provide the same full range as its predecessor, this design is effectively a modern bass trombone built down a perfect fourth. Although the contrabass has only appeared occasionally in orchestral repertoire and is not a permanent member of the modern orchestra, it has enjoyed a revival in the 21st century, particularly in film and video game soundtracks.