How many double reed instruments are in the orchestra?

Depends on how you define it. Oboe and bassoon are regularly in an orchestra, English horn and contrabassoon are used when necessary.

Better look through your notes. There is more than one way to interpret the question.

Double Reeded Instruments

"The orchestra"? as if there is only one variety?

This question is hard to answer, because it is vague.

There are, as others have said, four double-reed instruments in general use in the modern Symphony orchestra: Oboe, English horn, Bassoon and Contrabassoon. The english horn is actually the alto to the oboe's soprano, and the contrabassoon is a deep bass to the bassoon's tenor/upper bass. So you could consider the answer to be 2, oboe (family) and bassoon (family), or four, listing all four instruments. There are others which are used, some more often than others. The Oboe d'amore is a baroque instrument very rarely used in the modern orchestra. The baritone oboe is less rare, although I can only think of one piece right off the top of my head...but that piece is "The Planets" by Holst, which is very popular and often programmed! (Other double reeds exist and were used in bands during the last century or so, like the Sarrusophone, and other instruments exist with names like the double-reed instruments already given, like the Russian Bassoon, which is actually a wooden, brass-mouthpiece instrument with fingerholes instead of valves.)

If the question is, what is the total number of players of double reed instruments in 'the orchestra', then that depends on the orchestra. Mozart's orchestras got along fine on one bassoon and one oboe, most of the time. Handel's orchestras (admittedly Baroque era, not classical) often had two oboes and at least one bassoon, although there would only be one bassoon part written. The modern chamber orchestra is likely to have one bassoon and two oboes. The orchestras called "Symphony Orchestra" are most likely to have, at a flat minimum, two oboes and two bassoons. The normal manning for those positions in the World-class orchestras is 3 oboes and 3 bassoons, with the third desk player doubling english horn (for the oboist) and contrabassoon (for the third bassoonist.)

In short, the answer to the question is, "Its variable." The music that the orchestra plays demands certain numbers, and if the orchestra itself employs, for instance, three oboes and three bassoons and the music requires two oboes and one bassoon, only the first two oboists and bassoonists will go on stage. If the music is by Berlioz, though, the orchestra will employ, for the night, extras to fill out the written parts. And many smaller orchestras which have only two each will "pick up" extra oboes and bassoons as needed.

It's my guess that this is a homework question, and your teacher has given you this answer in the form that he/she expects to see it, though. It's worth your trouble to do some heavy memory-searching!

Good luck!

A major symphonic orchestra will typically have four different kinds of double reed instruments: the oboe, English horn, bassoon and contrabassoon. (As regards oboe, professional oboists can typically also play English horn). Usually there will be four players, though - two oboists and bassonists. One of the oboists could play English Horn if needed and one of the bassonists could play contrabassoon if needed, or they could bring in an extra instrumentalist to play the English Horn or contrabassoon if necessary due to the particular composition being played. The first oboe or first bassoonist is called "The Principle", but that's true of all the various sections, except the first violins, where the first violinist is called the Concertmaster, and his/her seatmate is called the Assistant Concertmaster. There are other doublereed insturments that are much less seldom played, like the heckelphone and oboe d'amour.

bassoon and oboe have double reeds so it depends how many bassoon and oboe players the ochestra leader can find