Sony's top V-FET amplifier, just as sweet sounding as good-looking.
Not that you'd need all the knobs - but the input/output clipping indicators were a nice touch. Just leave the tone controls out of the signal path :)
Providing you don't hook it up to real tortured electrostatics, it'll provide years of faultless operation. Providing you tweak here and there and upgrade a little, you're an even luckier fellow because V-FET transistors are the best audio solid-state devices ever made.
The TA-8650 is the first unit which sported Sony's new "ESII" design, the previous iterations of which you can see in the Invisibilia section of this website, the later iteration being, among others, the TA-N7B masterpiece, the PCM-1 industry shocker or the much later CDP-R1 & DAS-R1 bestsellers.
As all of Sony's 1st gen' V-FET units, the diodes and some resistors MUST be changed otherwise they'll take the amp section away and quite rapidly.
Said diodes are the reason why many TA-5650 died all too quickly in the 1970s and 1980s : the V-FETs had nothing to do with it.
Also, as for all 1st generation Sony V-FET, do NOT use a variac when powering the amplifier for the first time !