The woodwind family is made up of the flute, and instruments with a reed which are blown: clarinets, oboes, and bassoons. Usually there are at least two of each in the orchestra. There are other woodwind instruments, such as the double bassoon, the bass clarinet, the cor anglais (like an oboe, but with a curved reed and a lower and mellower tone) and the piccolo.
In the classical orchestra of Mozart and Haydn, oboes, flutes, and bassoons were used a lot, but the other woodwind instruments were developed later. The clarinet appeared later still, at the beginning of the 18th century. It was not used much until Mozart realised its possibilities, and wrote his clarinet quintet and concerto.
Brass instruments date back to beyond the Middle Ages, but animal horns being blown in pre-historic times were really the first ‘brass’ instruments. Today the brass family consists mainly of trumpets, French horns and trombones. There are other brass instruments which are not often found in the orchestra, but make up part of a brass band, such as the tuba, euphonium, and cornet. All of these instruments now use a system of valves and tubing to achieve their different notes, except the trombone, which has a slide. On any brass instrument the player can play several notes (harmonics) just by altering the shape of his lips. By making the tube longer, either by using valves or a slide, the whole range of notes can be played. Bach and Handel (baroque composers) wrote orchestral music with parts for the first kind of trumpet, and the orchestra of Haydn and Mozart used horns, as well as the new trumpet with keys and valves. Haydn wrote a concerto for this instrument soon after it was invented, and Mozart wrote four well known horn concertos. Trombones were not used much until Beethoven’s time, but from then on the brass section of the orchestra became more and more important.
The main percussion instruments in the orchestra are the timpani (or kettledrums). They were originally military instruments, played by soldiers on horseback, and were borrowed by orchestras in the time of Bach and Handel. These drums are tuned, unlike other drums in the percussion family, so orchestras use two or three instruments, each tuned to a different note. Until Beethoven’s time the timpani only played in the loud parts of a piece, often when the trumpets were playing. But Beethoven encouraged their use during the soft passages too, instructing the timpanist to play rabid beats softly. In this way the timpani could play a continuous soft note, which proved to be very effective. Gradually the timpani were used more and more, until today there are often several of these playing in an orchestra and sometimes more than one player for them. There are two other main types of orchestral percussion: the unpitched sort (instruments which do not play any particular note), such as other drums, cymbals and triangles; and pitched percussion, such as glockenspiels, xylophones, etc. These other instruments have not been used in orchestras very much until more recent times.