Professor: Douglas Repetto, douglas@music.columbia.edu
TA: Johnathan Lee, jlee@music.columbia.edu
Our Motto: "Why, then how."
First we'll finish with the piece presentations from thursday. Then we'll
continue with our current topic:
We'll revisit some of the quesions on the What Is an Algorithm? page and talk about how they relate to the pieces you presented last week. Then Johnathan and Douglas will present a few algorithmic works, going into some detail on how they work and the process by which they were developed.
Johnathan:
Algorithms as a musical calculator ("deterministic" algorithms)Excerpt from Tristan Murail's Desintegrations: With the software OpenMusic, we can see a mockup of the procedures designed to generate an accelerating sequence of chords with progressively inharmonic content from a reference harmonic spectrum. Note that this particular procedure is only used for one short passage in a 10-15 minute piece that using a bunch of different procedural operations)
Using algorithms to present a range of possibilities ("indeterministic" algorithms)
OpenMusic excerpt from Murail's Desintegrationsa) Generating syntactically coherent variations of a given musical passage using the LZ algorithm in OpenMusic. This example uses a MIDI transcription of Miles Davis' Blue in Green, creating reordered variations according to parameters set during each particular iteration of the operation.
Using the LZ algorithm in OpenMusic
b) Using algorithms to model Iannis Xenakis' stochastic operations in OpenMusic. In these examples, algorithms generate results using weighted probabilities and distributions in order to organize events and pitch material.
Herma
Achorripsis
c) Using Reaktor to create variations of a sample sequence based on a set of parameters in a live performance setting. This is an example of using different operations and variable parameters to generate different results in a realtime performance setting.
Douglas:
One simple idea, many possible expressions. Here are two of my simple counting pieces, both using a technique called "Gray code". Although based on the same idea and technique, the pieces explore in different directions. (And then one piece by Kaiser/Eshkar that brings up an interesting question from last week.)Counting toward the infinite, or at least the unknowable:
allPossibleImages. See also John F. Simon Jr.'s Every Icon and innumerable other "monkeys typing Shakespeare" pieces.
Counting for completeness: Counting Piece for Larry for Soloist and Algorithm.
A non-algorithmic piece that sure looks algorithmic:
Pedestrian by Paul Kaiser and Shelley Eshkar. (Harking back to the question: "What does it mean if you're not sure whether a work is algorithmic or not? Does the meaning of the work change?")
Your research assignment:
Find an algorithmic artwork that interests you, and poke around to find out some specific information about how it works and the algorithms that drive it. What's interesting about the algorithms? Do they matter? Pick a couple of the questions from the What is an algorithm? page and give us some thoughts/answers. (Try to focus on works that are clearly and purposefully algorithmic.)