That would be pretty blantant, but I suppose anything's possible. Even a subtle level or equalization difference will make a recording sound "better" or "worse" depending on what it's compared to. The vast number of consumers wouldn't know the differences they are hearing, just that one sounds "different". In my experience, a good recording will sound good no matter how many bits it is using or what the sampling rate, and a bad recording will likewise sound bad regardless. I don't think you heard that CD that I circulated awhile back where I took a cut from the Columbia Legacy CD of "Kind of Blue" and made reductions to 12 bits and 8 bits, then spliced these sections together with unaltered 16 bit so that they switched seamlessly. I didn't exactly get a flood of correct answers from people who could tell correctly when each switch was made.