Simple analogy lang audio. The reason why marami nagsasabi na sobra ganda tunog ng Sansui because they have tried and heard other vintage brands like Pio....r, Lu...an, Ke....d and ended up liking Sansui. I agree not all models of sansui are good sounding, pero when you get the chance to hear specific models, I'm sure game ender.
I myself was a trying hard hobbyist to high end audio before. I used to own Krell KSA 50, and I still have some brands from my amp collections, pero when I heard the vintage sansui amps BAM!!!! yun yung sound na gusto ko. Simple principle lang audio " Cause and Effect", siyempre pag maganda tunog automatic sasabihin ng listener na maganda, mahirap magsinungaling sa sarili ha ha.
But again, nobody is pushing the brand sansui here, it's just so happen sobra ganda lang talaga tunog.