Hmmm. Recordings with a bigger bottom end? Why would that be the case, do you think? I can understand where a young person with very good hearing might conceivably hear a difference beyond 22KHz (I'm stretching things, I know), but CD is well nigh perfect down to 20Hz. There shouldn't be *any* difference in bass response between the two formats. I think there are of great SACD recordings because great sound is the value proposition of the format, but I just can't hear the format differences. Are you actually referring to format differences, that you can hear the difference between the layers on hybrid SACDs?