Most older amps especially receivers including even the Sansui have limited power supplies in order to fit so much circuitry into the box without severe noise issues.
Compare to a current day Bel Canto c5i all digital integrated amp or similar c7r receiver which delivers 60 watts to 8 ohm and doubles to 120 into 4, meaning it is capable of driving most any speaker well even those that present difficult loads which these days is many and there was typically some background noise in play with most vintage receivers including the Sansui. Not a pitch black background like a C5I. Plus the modern Bel Cantos are about the size of a shoebox and much lighter and easier to handle than most similar powered vintage receivers.
C5i uses latest Class D amp and power supply technology to be able to do that in a smaller box without large power transformers, heat sinks, etc. it is also dead quiet. Most vintage receivers were not even close. The 9090db ( I remember it well, one of my favorites of the day) might go louder with 120 w/ch into 8 ohm perhaps but will not do as well with more difficult loads meaning sound quality is compromised.
So lots of technical innovation enabling more with seemingly less these days. Not to mention digital as well as traditional analog line and phono level inputs and built in DAC.
