I measured a different sample of the Naim NAP 250, serial number 518784, than that auditioned by Martin Colloms. I performed the measurements with my Audio Precision SYS2722 system after preconditioning the amplifier by following the CEA's recommendation of running it at one-eighth the specified power into 8 ohms for 30 minutes. At the end of that time, the cooling fan on the rear panel had turned on but the sidemounted heatsinks were very hot, at 127.1°F (52.9°C), and the top panel was only slightly cooler, at 116.4°F (46.9°C).
The Naim NAP 250 preserved…