tested the Primare A35.8 with my Audio Precision SYS2722 system. As the A35.8 has class-D output stages, all measurements other than frequency response were taken with Audio Precision’s auxiliary AUX-0025 passive low-pass filter, which mitigates noise above 80kHz and eliminates noise above 200kHz. (The relatively high levels of ultrasonic noise emitted by class-D amplifiers would otherwise drive the analyzer’s input into slew-rate limiting.) Without the filter, 325mV of ultrasonic noise was present at each pair of loud-speaker terminals, with a center frequency of 396kHz. Because the AUX-0025 filter is a two-channel device, I could
