The Sansui SC-737 is a stereo preamplifier that was part of Sansui's product lineup in the late 1970s. It features a low distortion design and offers various inputs for connecting different audio sources. The SC-737 includes tone controls, a loudness switch, and several outputs for driving amplifiers. It is known for its build quality and performance, making it a popular choice among audio enthusiasts. The unit is characterized by its classic design with a distinctive analog interface, including knobs and switches, contributing to an engaging user experience.