Sansui 5011 (c. 1971)

The Sansui 5011 was a stereo preamplifier. The only period record of it is a single listing in HiFI-Stereo (1971, p.33), where it appeared as a new model alongside the 5012 stereo power amplifier. Its big feature was Sansui's SEA (Sound Effects Amplifier) control system. That is a multi-band equalizer stage per channel, adjustable in 2-dB steps over a ±10 dB range at eight spot frequencies: 60, 150, 400, 1,000, 2,000, 4,000, 6,000, and 15,000 Hz.

The same listing gives an aux-input frequency response of 10 Hz-100 kHz ±0.5 dB and a 3 V output from 10-70 kHz. The inputs are aux and tuner at 170 mV, moving-magnet phono at 3 mV (100 kΩ) or 1 mV (50 kΩ), tape head at 1.2 mV, crystal cartridge at 120 mV, and mic at 2 mV. The 5011 accepted 100-240 V, 50/60 Hz, and measured roughly 6″ high × 19″ wide × 13¼″ deep. A $699.95 figure appears nearby in the listing, but the page's OCR makes it unclear whether that price belongs to the 5011 or the companion 5012 power amp.

Beyond that one advertisement, the record is thin. No service manual, independent test report, or production history has surfaced in the Archive's search. If you own a 5011, the basics worth preserving are its SEA tone-control system and its role as the front end of a separates system in Sansui's early-1970s lineup.