In fact, here's a test I made for someone on another forum who was claiming to have golden ears...they never replied to me.

One of these files is the original 24-bit version. One has been truncated to 16-bit (not even dithered). One has been converted to a 320 kbps CBR MP3, and back into a 24-bit wave using MADplay. And another an "extreme" VBR MP3, then simply decoded with Lame to a 16-bit wave. They've all been padded back up to 24-bits, so the file sizes are the same.

Tell me which is which.
Pioneer VSX-1018AH-K, PDP-5020FD, DV-79AVi
Axiom M22s, VP150, QS8s
Sony PS3, surround backs