Cornelius Cardew’s Treatise (1963-67), is quite probably the biggest and most beautiful piece using graphic notation ever written. And because Cardew left Treatise to be interpreted freely —there are no instructions — performances range from the strictly dutiful (reading left to right, up for high, down for low, agreed responses to certain symbols such as numbers or circles) to the eccentric.
Over the years students in various experimental and notation classes I have taught have come up with some really fine Treatise interpretations. One version for which I hold fondness and which exists on the web is by a former notation student, Ben Kennedy, who realised page 92 of Treatise as an assignment. Now I can’t remember the exact criteria he used (if you read this, Ben, do tell us!), but his realisation has the practicality and the ingenious social approach to indeterminacy that occurred in the best work of the Scratch Orchestra. As I remember it, Ben used friends and flatmates who were not music students, but were enthusiastic electric guitar players. He explained the piece briefly, but (I think) gave no strict instructions for the interpretation of the page (other than to give them a time frame to do it). And here’s the kicker: he contacted and recorded each of the four guitarists separately, then combined them for the ‘performance’ (actually, more like record production or minimalist mixing), so that what comes out in total could not have been predicted by each player. It’s a kind of obscure heterophony, I suppose, given their responses to the same stimulus. But since the guitarists use a soundworld typical of their kind, whilst avoiding cliché, it’s just a happy version of Treatise.
Here it is (there are a couple of electronic noises at the opening, and then it starts):