During my tenure as a Stereophile writer, I've reviewed a lot of integrated amplifiers. The mostly moderately priced integrated machines I've reviewed have included the Heed Audio Elixir ($1195), Luxman SQ-N150 ($2795) and L-509X ($9495), NAD C 328 Hybrid Digital ($549), Octave Audio V 80 SE ($10,500), Rega Brio ($995), and Schiit Ragnarok 2 ($1799 as equipped). Regardless of price, all these integrated amplifiers engaged my senses and made engaging, dynamic, colorful music from LP grooves and ones and zeros.

Talk about a Scarlet Letter. The term class-D amplification, which describes PS Audio's new M1200 monoblocks, exists only because another amplifier innovation had already parked in the "C" space. Soon after appearing in high-performance audio gear, class-D became synonymous with "digital amplification" in part because, like early CDs, many listeners found the sound glary, hard, and unpleasant. Besides, class-D is related to "pulse width modulation" and requires a low-pass filter to block high-frequency pulses—that sure sounds digital. But they're not (see Bruno Putzeys sidebar).