The title Dialogues and Contrasts describes the nature of the exchange which takes place between the performer and the materials committed to tape. In the first movement the exchange is more in the nature of an argument. Though initially each side appears to favor an independent thematic course, as the movement progresses the performers engage in direct response to the statements on tape. The second movement is more subdued and reflective, with many solo passages, particularly from the French horn. Tape joins from time to time with its own version of the fragmented melodic lines. In the last movement it appears as if the instruments and tape each decided to go their own way...

Colloquy is intended as a fun piece—a musical and verbal interplay between the orchestra, conductor, and tape recorder. In 1954, Otto Luening and I juxtaposed pre-processed sounds on tape with live instrumental ensembles for the first time in our joint composition Rhapsodic Variations for Orchestra and Tape Recorder. This combination is now practiced frequently, though predominantly in conjunction with the smaller chamber groups or with the individual instruments. But many an eyebrow is still raised at the idea of having a recording-playback device sharing the platform with musicians. So Colloquy gives a chance to the tape recorder to plead its case in public debate. The final proof of the legitimacy of this union must, of course, be a musical one.. — Vladimir Ussachevsky