OK, I’m old

Apparently it was this week in 1982 Sony launched their first CD Player

Sony CD-101

Mine still works, its had a re-cap over the years, but that’s about it

Playing an SQ Quad CD. In the rush to market some early CDs accidentally had Quadraphonic Masters used

Sony SQ Decoder SQD 2020

@avavsystems Ah Quad. Grew up with a neighbour who had a quad setup. I read that some classical cassettes did a similar thing (from quad masters) but can't quite imagine how poor any attempt to decode them might be.
@emsquared it was ok-ish. I’ve picked up a couple.