Stereo 150

About the Stereo 150

The Dynaco Stereo 150 is a basic two-channel power amplifier employing all silicon semiconductors, including 24 transistors, 2 zener diodes, 16 diodes, and 2 thermal sensors. It features a full complementary symmetry output design and is direct coupled except for the input network. The amplifier delivers 75 watts per channel into 8 ohms in stereo mode and can be internally restrapped for monophonic operation at 150 watts into 8 ohms. It has very low distortion (0.25%) and a wide frequency response (20 Hz to 20 kHz), with a damping factor of 50 and a signal-to-noise ratio of 95 dB. Protection includes multiple fuses, electronic volt-amp limiting, and thermal sensors to prevent overheating. The amplifier is designed to drive a wide variety of loudspeaker loads, including electrostatics and complex crossover systems, with minimal listening fatigue due to its low crossover distortion. Dimensions are approximately 14.5 x 13.75 x 7 inches, and it weighs about 29 lbs. It was released around the early to mid-1970s and remains a respected vintage amplifier for audiophiles.