a computer-assisted composition program

MP1, written by Sever Tipei, was first used in 1973. Although its underlying structure remained the same over the years, MP1 has been evolving continuously, a frame-work in progress to which new features are added. Based on the proposition that the sounds of a composition can be described as entities in a multidimenssional vector space, the program has three interlocked layers: stochastic distributions, sieves or logical filters, and Markov chains.

Any number of two or more sound parameters (sound characteristics) can be defined for an arbitrary number of parts (streams of events); by default, the first parameter is assumed to be time. For each parameter, equivalence relations mod m of the form: are described where n is the equivalence class and m is the size of the equivalence class. This way, control over details is exerted through n while the broader aspects (such as octave or register in the case of pitch) are controlled through k. The main loop of the program assigns values for each sound parameter by matching the probability of various elements on a list of possibilities with a random number. A choice is completed when all such values are assigned for an event.

MP1 is a comprehensive program in the sense that once the computations start, the user can not intervene until the piece is finished and then, either accepts or rejects the result. This way, the composition is treated as a process which, once triggered, is capable of continuing on its own, like a natural phenomenon. In the author's mind, this approach

  1. elevates the act of composing with computers to a higher or meta-level,
  2. insures its integrity of the process, and
  3. uses the computer as a collaborator in stead of a dumb slave.

Stochastic layer:


Markov chains:

The 100% option:


Entering data:

Pieces produced with MP1:


  1. MP1 Revisited: AGA MATTER for Piano and Computer Generated Tape, Proc. 1994 Int'l Computer Music Conference (Aarhus, Denmark; September 1994), International Computer Music Association, San Francisco, CA, 1994, pp. 3-6.
  2. The Computer, a Composer's Collaborator, LEONARDO Journal of the International Society for the Arts, Sciences, and Technology, vol.22, no. 2, 1989, pp. 189-195.
  3. (Super)Computer Produced Musical Manifolds, Contemporary Music Forum; Proc. Bowling Green State University New Music and Art Festival 10 Paper Sessions, Vol.1, (Mid-American Center for Contemporary Music, College of Musical Arts, Bowling Green State Univ., Bowling Green, Ohio; 1989), pp. 23-26.
  4. Manifold Compositions - a (Super)computer-assisted Composition Experiment in Progress , Proc. 1989 Int'l Computer Music Conference , (Ohio State Univ., Columbus, Ohio; November 1989), International Computer Music Association, San Francisco, CA, 1989, pp. 324-327.
  5. MAIDEN VOYAGES - a Score Produced with MP1, Computer Music Journal, vol. 11, no. 2, M.I.T. Press Journals, Cambridge, MA., 1987.
  6. MAIDEN VOYAGES - a Score Produced with MP1, Proc. 1985 Int'l Computer Music Conference, (Vancouver, B.C., Canada; August, 1985), International Computer Music Association, San Francisco, CA, 1989, pp. 259-265.
  7. Solving Specific Compositional Problems with MP1 , Proc. 1981 International Computer Music Conference, (North Texas State Univ., Denton, Texas; November 1981), International Computer Music Association, San Francisco, CA, 1989, pp. 101-109.
  8. MP1, a Computer Program for Music Composition , Proc. Second Annual Music Computation Conference, (Univ. of Illinois, Urbana, Illinois, November 1975), pp. 68-82

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