I bought a stack of these in Paris and just got home day before yesterday. Popped three of them in the system today and played them through. The performances are wonderful, can't fault them (was not familiar with these particular discs until the news about them a few months ago). I did notice some hissing that I haven't noticed until now with any other SACDs in my collection. I know these tapes are half a century old but I guess all the hype surrounding these releases made me think the background tape hiss would be less than what I've heard. Am I being too unrealistic? I wouldn't trade them (got a great deal) but to someone who's listened to them on vinyl or CD, do these represent a serious step up in sound quality? Just curious from an historical perspective.