Depends on what you mean by new age music. The only answer in my opinion is Jimi Hendrix as he not only helped change how people used distortion in rock music, but also that he was extremely prolific in multi-track recording.
Virtually every style of music uses multiple tracks during the recording process. Software has obviously made it easier since back with Jimi was doing it, he actually had to use MULTIPLE recorders with old school tapes.
As a matter of fact, you can pretty much credit Hendrix for influencing every genre of music to follow his short career. Guitar playing aside he did more for music than pretty much anyone besides Robert Johnson/Leadbelly et. al. those old school blues artists.
