EUTERPE-LISP: A LISP System with Music Output

Abstract

EUTERPE (Ai memo no. 129) was designed as a "real-time music program" which would interpret music described as "voice-programs" in DDT. These voice-programs consisted of note words, description of tones to be sounded, and control words which determined the parameters of pitch, tempo, articulation and wave form and allowed for a subroutine feature and transfer within the voice-program. It had been hoped that complex musical forms could be described in terms of a few collections of note words and sequences of control words. However, musical variation and development is more subtle than the developmental power of these control words. Any transformation of musical material may be expressed as a LISP function; therefore, the control words were abandoned and EUTERPE was linked to LISP. The voice-programs would be written and loaded by LISP and played by EUTERPE. The principle function in the system is LOAD which takes two arguments: 1) an absolute location in core and 2) a list of note words. The note words are translated into EUTERPE-readable code and loaded into the proper voice program. The addresses of the first location of each if the six voice programs are SETQed by the system with the names VOICE1, ..., VOICE6. The value of LOAD s the next file word in core, so a series of lists may be loaded by bootstrapping.