"The migration of the tools of computer music from large specialized systems to 'personal' machines has become a common theme in discussions of art in the new century. Regardless of genre or style, the newly liberated composer faces similar questions regardless of their area of interest: how does one use a computer as an instrument? William Kleinsasser's Available Instruments provides two possible answers. His new c74 release includes two works that match high levels of musicianship from ensembles and soloist with his own compositional concerns about the relationships between timbre, performer, and machine. The title track is a duet for piano and computer whose energy lies in the tectonics of a complex player-controlled interplay between 'memories' of a performance and the human performer. The Double Concerto embodies a different strategy, where the performers collectively vitalize a complex system of memory and transformation composed of interactions with pre-recorded, recalled, and reordered versions of performance. It is music with the scale and drama of a great soundtrack -- two carefully and fully imagined sonic worlds destined to reward the serious and regular listener."