This paper presents a means of modulating timbre in digital sound synthesis using additive processes . A major portion of the paper is a computer program, written in Pl/1, which combines this additive method of timbre modulation with several other sound manipulation ideas to form a compositional program. This program-which is named CART for Computer Aided Rotational Translation-provides input for the Music 360 digital sound synthesis program. The paper contains three major parts: (1) a discussion of the CART program's evolution; (2) a manual describing in detail the use of CART; and (3) two tape compositions realized using the program. An appendix contains the program listing and listing of the input cards that were used to produce the two compositions.

New York City: A Collage of Cultures is a single-movement programmatic orchestral work that features polytonality, prallelism, sound-mass, micro-tones, polychordal rhythmic ostinato, neo-impressionism, and folk themes and anthems from sundry cultures and nationalities. The simultaneity of contextual material at one point necessitates the employment of three conductors. The composition portrays America as a "melting pot" through its busiest immigration center, itself a microcosm of diverse international elements. This is achieved by the depiction of three different settings: a boat sailing from a foreign port, bound for New York Cty; New York itself in all of its awesome fury; and a capsule image of a conglomerate of turn-of-the-century emigrants and their interaction throughout the voyage.