ang balita ko from andrew sevilla of phasetron is that sansui used to be a manufacturer of power supplies, kaya yun ang specialty nila at nag carry over sa amplifier products ang expertise nila dun.....
Sansui used to be a power transformer manufacturer after WWII, kaya talagang nandoon ang galing nila. If you open your Sansuis, especially the Alpha series, the toroidals have the "vintage" description on them. That's because the company took power supply design seriously, could be patented, a la Krell. Alpha 907 amps have weights ranging from 28 kgs to 35 kgs, I think, approximating the heft of Krell's low to middle models. I opened my Sansui Alpha 907 and Accuphase E302 just last week and the power amp designs of the two were very similar to Krell's. Accuphase's power caps, however, are really big - three times those of Sansui's although my Alpha 907 has four, dalawa lang ang Accuphase. Sabi ko nga kay Sir Akyat sa PM, yung sa Accuphase parang specialized audio but industrial grade - mukhang mahirap maghanap dito sa Pinas para ma-repair ang unit niya. Biro lang, Sir!
Sansui also started with tube amps, like other audio old-timers, but shifted to SS. Their chief designer in the '70s was fascinated with the old Sansui tube sound, so, he tried to alter their amps' circuitries starting with the first 907 in mid '70s to mimic the sound of the tube amp (sayang meron dito sa Davao na original AU-907, P3K lang last month, hindi ko pa binili agad, naunahan na naman ako.) This time, it's high-powered (unlike the old Sansui tube power amps) and without the hum even at high volume (which is a problem for many tube power amps). This is the same path taken by Dan D' Agostino of Krell and Bob Carver of Sunfire (formerly of Carver Corp.). Carver's expensive Silver Seven amp is tube but SS-sounding amp, which some said is even sonically better than the famous (or infamous) Ongaku valve amps that retail from $100,000 t0 $300,000 per unit.