Free improv

Free improvisation
Stylistic origins	Free jazz Avant-garde jazz 20th century classical music Serialism Aleatoric music
Cultural origins	Mid-1960s United States, UK, and Europe
Derivative forms	Electroacoustic improvisation

Free improvisation or free music is improvised music without any rules beyond the logic or inclination of the musician(s) involved. The term can refer to both a technique (employed by any musician in any genre) and as a recognizable genre in its own right.

Free improvisation, as a genre of music, developed in the U.S. and Europe in the mid to late 1960s, largely as an outgrowth of free jazz and modern classical musics. Exponents of free improvised music include saxophonists Evan Parker, Anthony Braxton, Peter Brötzmann and John Zorn, drummer Christian Lillinger, trombonist George Lewis, guitarists Derek Bailey, Henry Kaiser and Fred Frith and the improvising groups Spontaneous Music Ensemble, The Art Ensemble of Chicago and AMM.

In an atonal context, free improvisation refers to where the focus shifts from harmony to other dimensions of music: timbre, melodic intervals, rhythm and the spontaneous interaction between musicians. Although performers may choose to play in a certain style or key, or at a certain tempo, conventional songs are highly uncommon in free improvisation; more emphasis is generally placed on mood, texture or more simply, on performative gesture than on preset forms of melody, harmony or rhythm. These elements are improvised at will, as the music progresses.

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