Credo in Us di John Cage.

Dated: New York, July, 1942. Revised October 1942
Instrumentation: 4 performers: pianist; 2 percussionists on muted gongs, tin cans, electric buzzer and tom-toms; one performers who plays a radio or phonograph;
Duration: 12′
Premiere and performer(s): August 1, 1942 at Bennington College in Bennington, Vermont, performed with the choreography by Merce Cunningham and Jean Erdman

The work was composed in the phraseology of the dance by Cunningham and Erdman. For the first time Cage uses records or radios, incorporating music of other composers in his own works. He suggests music by Dvorak, Beethoven, Sibelius or Shostakovich. Cage describes the work as a suite with a satirical character.
Jean Erdman recalls that for the first performance a ‘tack-piano’ was used (a piano with tumbtacks inserted onto the felt of the hammers). The pianist mutes the strings at times or plays the piano body (as a percussionist).

FONTANA MIX and ARIA by John Cage are two separate pieces, although capable of being performed simultaneously as has been done and recorded here.
FONTANA MIX is a composition indeterminate of its performance. It is derived from notation CC from Concert for Piano and Orchestra. The score consists of 10 sheets of paper and 12 tranparencies. The sheets of paper have drawings of 6
differentiated (in thickness and texture) curved lines. 10 of the transparencies have randomly distributed points (the amounts of points on the transparencies are 7, 12, 13, 17, 18, 19, 22, 26, 29 and 30). Another transparency has a grid, measuring two by ten inches, and the last one contains a straight line (10¾ inch).
By superimposition the performer creates a structure from which a performance score can be made: One of the tranparencies with dots is placed over one of the sheets with curved lines. Over this one places the grid. A point enclosed in the grid is connected with a point outside, using the straight line transparency. Horizontal and vertical measurements of intersections of the straight line with the the grid and the curved line, create a time-bracket and actions to be made.
Fontana Mix may be performed with or without parts written for the Concert for Piano and Orchestra, Aria, Solo for Voice 2 and/or Song Books. Tone-control may be regulated using Cage’s composition WBAI.
Cage composed other works using the material from Fontana Mix: Water Walk Sounds of Venice, Aria, Theatre Piece and WBAI. Cornelius Cardew composed his Solo for Guitar using the same material.
In February 1959 Cage prepared a version for 2 tapes of the work at the Studio di Fonologia in Milan, with technical assistance of Mario Zucchen.

The Aria’s score consists of 20 pages of music, each page being sufficient for 30 seconds in performance. Pages may be performed over longer or shorter time-ranges to create a program of a determined time-length.
The Aria may be performed as a solo, or with Fontana Mix and/or with ahy parts of the Concert for Piano and Orchestra.
The text employs vowels and consonants and words from Armenian, Russian, Italian, French and English. The notation consists basically of wavy lines in different colors and 16 black squares denoting “non musical” vocal noises. The colors denote different singing styles, to be determined by the singer.