The bassoon is a long pipe, doubled in half, made of wood, with many keys. The bend in the pipe makes it possible for musicians to play it comfortably. If it were straight, the bassoon would be around 9 feet long! Like the oboe, the bassoon uses a double reed, which is fitted into a curved metal mouthpiece. There are 2 to 4 bassoons in an orchestra and they have a similar range to that of the cello. Bassoons usually play lower harmonies, but you will sometimes hear their hollow low notes featured in a melody. You play the bassoon by holding it upright and blowing through the double reed. The air travels down the tube and then makes a u-turn and goes up and out the top. Just like the oboe, you use both hands to press on the keys to open and close the holes and change the pitch.
Imagine a longer bassoon with a wider pipe. The contrabassoon is the grandfather of the wind section and is so much larger than a regular bassoon that its tube is doubled over twice to allow the player to hold it. It takes a lot of breath to make sound come out of such a long pipe! The lone contrabassoon plays the lowest notes in the entire orchestra.