As a keyboardist, Hirschfelder has been a member of various groups including the jazz fusion band Pyramid, rock band Peter Cupples Band (1980), pop rockers Little River Band (1983-1986), Blowout, Dragon (1987, 1989), adult contemporary singer John Farnham's backing band (1986-1992),[REF] and jazz fusion supergroup CAB [REF].
In 1980 Hirschfelder joined the Peter Cupples Band, Cupples had just left his soul-pop group, Stylus, and formed the rock group with Hirschfelder on keyboards, Virgil Donati on drums, Ross Ingliss on guitar and Robert Little on bass guitar [REF].