English manufacturer Chord Electronics is known for its sophisticated CD players, which use sophisticated DACs. Indeed there was a huge picture denoting Chord's latest-generation DAC, the QBD 76, at the center of the back wall. As my beat was amplifiers, Chord's designer, John Franks (pictured above), spent the next 30 minutes walking me through the design of Chord's latest amplifier, the SPM 1200 Mk.II ($14,000), a solid-state, 350Wpc stereo mode. The amplifier sits at the bottom of the short stack of audio equipment John is leaning on. He explained that the amplifier has a high-frequency, 2kW, switch-mode power supply, and uses an output stage based on dual-die, lateral-structure MOSFETs with a soft turn/on-turn/off characteristic. This allowed John to use a sliding class-AB design.
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