Just for the record Dave to shed more light to those who may be interested, Carlos recorded earlier as Walter the first 2 albums and later had a sex change during the well tempered sythnesizer album the story is as follows
Walter Carlos
Profile: Electronic musician Walter Carlos was born in 1938 in Pawtucket, Rhode Island (USA) and had a big interest in both music and technology. At the age of ten he composed his first piece and at 14 he build a small home computer. Three years later he assembled an electronic music studio and created his first electronic musical composition, manipulated with some tape recording.
At the Brown University (1958-1962), Carlos studied music and physics and taught electronic music; at the Columbia University (1962-1965), he did extensive work at the Columbia-Princeton electronic music center and in that period, Walter Carlos assisted the famous director Leonard Bernstein in a concert of electronic music at the Philharmonic Hall, Lincoln Center, and also managed to get two of his compositions, Dialogues for Piano and Two Loudspeakers and Variations for Flute and Electronic Sound, commercially recorded.
With the wish to develop an electronic sound producing unit which could validly be called a musical instrument, Carlos began a collaboration with engineer Robert Moog in 1966. The result was a prototype of Carlos' special synthesizer on which he performed and recorded his realizations of Bach and other composers (the Switched-On series) and his music for the musical score of A Clockwork Orange.
In 1969, he had a sex-change becoming Wendy Carlos, and has been known the rest of her career with this name. This means that the artists name Walter Carlos refers to a specific period of time and a small set of releases, especially the first Switched-Ons. Although this isn't really noticeable now, it's obvious that the sex-change must have a big impact on the musical career, at least from a commercial point of view.
Even Wendy's official website doesn't say much about this period, and that's a pity, because it was very important for the development of 'Electronic Music', the synthesizer as musical instrument and what we now call 'Minimalistic': the (re-)search for the boundaries of music and sound. Music, more or less, from a scientific point of view. Of course, in the 70's a sex-change wasn't very well-known and accepted as it is today. For more information about this artist, especially the later period, see Wendy Carlos.