[7] In 1971, Sansui introduced the Quadphonic Synthesizer QS-1, which could make simulated four-channel stereo from two-channel sources.

Sansui developed the QS Regular Matrix system, which made it possible to transmit four-channel Quadraphonic sound from a standard LP.

Some Sansui receivers could also play the most advanced four-channel system: CD-4 (or Quadradisc) by Japanese JVC and American RCA.

[10] In the late 1970s, the first-generation '07' models included the dual-mono power supply AU-517 and AU-717, and the second generation featured the updated AU-719, 819, and 919 were released.

[11] In the UK around 1982, the Sansui AU-D101 amplifier and its more powerful sibling the AU-D33,[12] were acclaimed by audiophiles[13] and were so well matched[citation needed] to a pair of KEF Coda III speakers that they could be bought as a set from some outlets.

[3] Sansui began to lose visibility in the United States around 1988, and then focused on manufacturing high-end components in Japan.

The company began to manufacture high-end television sets and other video equipment, but ceased exportation.

The current manufacturer of the rebranded sets is Orion Electric, based in Osaka and Fukui, Japan.

Lately Sansui had developed a turntable, P-L95R, with a handling similar to CD-players; it allowed to play both sides of the record without turning it.