Classical music is driven by the composer; jazz is driven by the performers. In jazz, rhythm plays an important role, but in classical jazz it is a subtle element that is definitely less prominent. For decades, composers of jazz and classical music have looked the other side of the fence. Classical composers envy the melodic enthusiasm, spontaneity and open emotion of improvisation; jazz musicians focus on the major scale, on the colourful and rhythmic flexibility, and on the respect given to classical music.
Jazz and classical music are two very different musical genres. But what makes them different? Jazz is often associated with improvisation. This means that the musicians in a jazz band create their music on the spot, rather than playing from a predetermined score. This results in a more relaxed and spontaneous sound.
Jazz music often features a combination of brass instruments, woodwind and percussion. Great jazz bands rely heavily on brass instruments, especially saxophones, which classical composers rarely use, and the vertical double bass in jazz is usually pulsed rather than arched, as is often the case in classical music. Classical orchestras feature woodwind, brass and percussion instruments, but they also include bowed string instruments such as violin, viola and cello, which are rarely used in jazz. In general, there are between 50 and 100 musicians who make up a classical orchestra.
As another example of the differences in instrumentation, a jazz piano trio usually consists of a piano, a double bass and a drum, while in classical music it usually consists of a piano, a violin and a cello. The piano is a central instrument of both classical and jazz music. Primitive jazz music was played in small ensembles that used clarinet, tuba, cornet, baritone, drums and piano.