New to the Heptode line of guitar effects: The Virtuoso Phase Shifter. The Virtuoso is a boutique recreation of the original Maestro PS-1A Phase Shifter, as used in the 1970s by keyboardist John Paul Jones (Led Zeppelin) and guitarists Steve Howe (Yes) and Ernie Isley (Isley Brothers), among many others. Footswitches…... Click for more