I made the piece on May 11, 1969, on my drafting table, dividing the page into six horizontal bands demarcated with dashed lines; then drew thick lines to indicate sounds (placed high or low to indicate pitch, of varying thicknesses to indicate loudness, of varying length to indicate duration), and connected these with thin straight lines to indicate voice-leading, two melodic lines to each band.
The instrumentalists can play from left to right or from right to left; when any system is completed, they pause or do not before beginning any other. The performance begins and ends as seems right.
Screen is intended as a sound-curtain through which something else might be heard — another composition or two, or ambient sounds, or internal songs. Screen should therefore not be too insistant. It should be fairly slow and quiet. Not too much needs to be made to happen. It is unassertive, like any linear statement. It is cool, a little formal, rather conservative, but not plain or cold. The several systems can be played forward or backward, each taking about a minute. I prefer Screen played by three to six instruments, weighted more toward violas than violins, including contrabasses too if possible. (I would like to hear it performed by a capella chorus one day, or by an ensemble of trombones.)
Variations was composed six years later, in 1975, again a graphic score, this time based on a star map that had been used on a poster advertising an exhibition at the Oakland Art Museum. Here again I relied on an intuitively pleasing visual appearance to guide me to a pleasing sonic resolution; this time the size of the circles indicated loudness; the placement on the page indicated pitch; and since I was thinking of nonsustaining instruments like harp and percussion there was no reason to extend the lines to indicate duration.
I'm sorry the scores do not reproduce better here. You can hear Variations played on the harp, superimposed on a performance of Screen by a string quartet, here, as recorded in a live concert thirty-two years ago in San Francisco.