NAD 2150 Tested and 100% working state Cleaned A 2 x 50 watt hi-fi stereo Power Amplifier. With a high-voltage, high-current output stage enabling it to deliver well above its rated power to handle musical transients, and a 'soft clipping' circuit which gently limits the waveform voltage when the amplifier is driven beyond its rated power. On the rear, Main-In sockets for connection to a pre-amplifier, connectors for two pairs of loudspeakers, switches for Soft Clipping (On/Off), Bridging (On/Off) and a Speakers Impedance switch (Normal/Hi (≥ 8Ω)), the Hi setting can be used where one pair of speakers are connected and their impedance is at least 8Ω, this re-optimizes the amplifier for maximum power. Some models have a switched and an unswitched AC outlet and some a voltage selector. On the front, switches for Power, Speakers A, B, LED indicators for Power, Protection and Soft Clipping and a jack for headphones. Specification Speakers Impedance Switch Set: Normal Hi (≥ 8Ω) Continuous Average Power Output at 8 ohm 20-20K Hz both Channels Driven : 50 W 60 W Rated Distortion 20Hz-20kHz ...............: 100 THD 20Hz-20kHz from 250mW to 60W : Frequency Response, 20Hz-20kHz .......: ±0.5 dB Frequency Response Range -3 dB ........: 10Hz-35kHz