A one-movement orchestral piece, the form of which is based upon programmatic principles. They become different and difficult to perform and recognize. Chords are used for their color rather than function. Bi-tonality becomes popular. Timbre - Old instruments become popular.
String instruments become less popular.
Brass and percussion is used for color effects. Non-western percussion is used as well as the human voice as color instruments. Instruments are used in non-traditional ways in order for the composer to achieve the effect so desired. Texture - A renewal of polyphony. Polyrhythms are used as are heterogeneous ensembles.