Some redbook CDs sound much better than most any SACDs I've tried--admittedly that is very few (under 10). I have a Modwright 5400 with all the upgrades and it plays both formats beautifully. However, as with vinyl, there are some cds that sound better than the records and usually vice versa. There are some cds that were remastered that sound much better, and some are very thin sounding with zero dynamics. Music is exactly the same, but the sound can be another animal better or worse. I tried a Bob Dylan SACD and the sound was really not too good. IMO SACDs need to be listened to prior to buying as there is a BIG difference in sound quality from one album to the next. Due to the fact there as many excellent sounding CDs of music I really like, I only have 2 SACDs that I actually own--1 of which I don't really love the music but it sounds phenominal/the other sounds good for what it is, music from the 60's with a couple good cuts that I bought used and cheap. It sounds good compared to what I remember growing up and having a cheap record player and speakers--it ought to compared to the system I finally own. Music that has both great sound and is great music are a low percentage in any format.
Lastly, there is the possibility that your wife is so against your interest in listening to music on YOUR stereo that she SAYS she can't hear any difference so you don't feel compelled to buy any more expensive stuff. Why do I know this? Hummmm. Could it be personal experience? My wife can hear the difference on our less good sounding home theater system vs. the regular TV--but often says, "I can't hear any difference in the sound between OUR home theater and YOUR stereo downstairs." There is a night and day difference a tone deaf person would hear.
Lastly, there is the possibility that your wife is so against your interest in listening to music on YOUR stereo that she SAYS she can't hear any difference so you don't feel compelled to buy any more expensive stuff. Why do I know this? Hummmm. Could it be personal experience? My wife can hear the difference on our less good sounding home theater system vs. the regular TV--but often says, "I can't hear any difference in the sound between OUR home theater and YOUR stereo downstairs." There is a night and day difference a tone deaf person would hear.