Cobra (Zorn)

Cobra is an unpublished but recorded and frequently performed musical composition by John Zorn that was conceived as a system with very detailed rules but with no pre-conceived sequence of events, or game piece, for a group of musical improvisors and a prompter. Zorn completed Cobra on October 9, 1984. The composition consists of a set of cues notated on cards, and rules corresponding to the cues that direct the players what to do. The number of players, instrumentation, and length of the piece is indeterminate. Because there is no traditional musical notation and the players improvise, the piece may sound radically different from performance to performance.

As was commented upon in some length in a 2004 interview, Zorn has, with his own words, "deliberately chosen not to publish (or even write down) the rules" to his game pieces, being concerned with the importance of personal instruction. Despite this, photocopies circulate among musicians internationally, and there is even a clean printing of all the cue categories in a CD booklet (see recordings).

Cobra was first performed at Roulette Intermedium, which celebrated the work's 30th anniversary on November 29, 2014, at their location in Downton Brooklyn, with Zorn at the helm.

2 photocopied pages with cue categories and explanation of form. First page signed John Zorn (C) Oct 9 NYC. Second page titled "IMPROVISATION. John Zorn - "COBRA", annotated by SB".

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Wikipedia