After naval service in World War II, he moved to New York, where he attended Columbia University and worked as a jazz pianist before joining RCA Victor as a design engineer in 1949.
Pfeiffer also recorded contemporary artists, including the mezzo-sopranos Marilyn Horne and Frederica von Stade, and Xiang-Dong Kong, a young Chinese pianist.
Pfeiffer also produced recordings by the pianists Vladimir Horowitz, Arthur Rubinstein and Van Cliburn, the harpsichordist Wanda Landowska, and the soprano Leontyne Price.
In addition to Toscanini, Pfeiffer worked with Fritz Reiner, Leopold Stokowski, Eugene Ormandy and Charles Munch, and produced their initial "Living Stereo" recordings.
The individual tracks on the record are labelled "Warm-Up, Canon, and Peace, For Inharmonic Side-Band", "Reflection of a String, For Contraformer", "Drops, For Programmer and Sines", "Moments, Events for Parametric Blocks", "Take Off, For Metric Transperformer", "Forests, Modes for Alphormer and Set".