The bass oboe or baritone oboe is a double reed instrument in the woodwind family. It is about twice the size of a (tenor) oboe and has a deeper sound. Its part is notated in the treble clef an octave higher. A woodwind instrument is a musical instrument in which sound is produced by blowing through a mouthpiece against an edge or by a vibrating reed, and in which the pitch is varied by opening or closing holes in the body of the instrument. ... Modern Oboe The Oboe is a musical instrument of the woodwind double reed family. ...

Early bass oboes were either like bassoons, in that they had a boot joint and bocal, and some holes drilled obliquely, or they were enlarged English horns. The bass oboe as enlarged English horn concept survived, and such an instrument made by François Lorée caught Frederick Delius's fancy, during his time in Paris at the end of the 19th Century. When Delius returned to England, other British composers became interested in the bass oboe and wrote music for it, including Gustav Holst and Havergal Brian. It wasn't until the next century that a solo concerto was written for the instrument, by Gavin Bryars. Bassoon Playing range of a bassoon The bassoon is the tenor member of the woodwind family. ... Cor anglais The cor anglais or English horn is a musical instrument of the woodwind family. ... Frederick Delius (January 29, 1862 – June 10, 1934) was an English composer born in Bradford. ... Gustav Holst Gustavus Theodore von Holst (September 21, 1874 – May 25, 1934) was an English composer with Latvian (and some Spanish) roots. ... William (Havergal) Brian (January 29, 1876 – November 28, 1972), was a British composer. ... Richard Gavin Bryars (born 1943) is an English composer and double bass player. ...

Contrabass oboes have not caught on because contrabassoons are much more practical for the purpose.