The Mag AmpWorld’s First Switching Amp
John Devore was using this diminutive integrated amplifier, the German-manufactured Acoustic Plan Mag Amp, to drive his new high-sensitivity loudspeakers. According to Jonathan Halpern, the US importer, the Mag Amp uses a tubed voltage-gain stage and an output stage comprised of two small transformers with dual primaries. He described it as the "world's first switching integrated amplifier, and added that it was designed by Lars Lundahl in the 1960s. The 19 kg stereo chassis offers 15Wpc into 8 ohms and will cost $18,500. It played both a 1980s recording of Ella Fitzgerald and one of Stravinsky's Pulcinella Suite with great dynamics, speed, and detail. This is the kind of odd and fascinating gem one can uncover at the end of a day when one is too tired to rush out of an exhibit room, and instead collapses on the couch to listen.