It was with regret that I heard John Ulrick had passed away on May 20, 2015 due to complications from cancer. With Arnie Nudell
and Cary Christie, John was one of the founders of loudspeaker manufacturer Infinity, a company that, with Audio Research, Magnepan, Mark Levinson, and Threshold, epitomized the nascent High End that emerged in the early 1970s. After leaving Infinity, John Ulrick started Spectron, to manufacture class-D amplifiers.
Just by chance, I met with the John Ulrick, in Los Angeles in late 1987, when he was doing some design consultancy on a switch-mode power amplifier to be used with the Sumo Samson subwoofer. As I had my Walkman Pro with me, I took the opportunity to tape some background from John about the birth of Infinity and about switching/pulse-width-modulated/class-D amplifiersboy, can this man talk about switching amplifiers! The natural kickoff question was, How did Infinity get going?