Old school vs new school audio???

Need help. Got into the audio world in the mid 80's while stationed in Germany, US Air Force.  Brought home some great audio equipment for what I could afford at the time.  Trying to get back into it, but things just don't sound the same.  Lack of fidelity.  Have 2 x NAD 2200's I mono bridge.  Upgraded my Yamaha preamp to a McIntosh 6700 receiver thanks to my dad.  Have very nice Paradigm speakers.  Klipsch horns are on my bucket list.  Use audio quest cables.  Maybe I have lost my hearing, but I don't really believe that's the case.  Any input or guidance for me.  Thanks.