My Search for a Better Sound

My stereo set up is late 80's analogue: Pioneer receiver
, large full range Infinity speakers in front, 2 Philips fulls in rear,
fed by factory modified Apex 600 dvd player & stereo vcr.
I have resisted moving to 5.1 digital partly because I'm
not sure I would appreciate sound quality improvements.
A little used dvd "blue book"? feature is the ability to
pass 24/96 quality sound using analogue outs. I have nearly a dozen dvd's that use this
feature from Classics, Chesky, & Aix Records. Although all the dvd's deliver subjectively good
sound, I am not sure whether this is because of a carefully done recording/pressing.
I find the special repressings of 20bitK2 jazz disks to
be equally impressive. Verve re-issued very high quality classic jazz disks.
I did an a/b test at a local high end sound store with
two versions of the Herb Ellis "Seven Come Eleven"- one a cd, the other a 24/96 dvd.
Neither I not the salesman could discern a difference in sound between
these two disks. A caveat might be that this was a repressing.
Aix Records does what amounts to direct to disk original recordings
& adds many vidoe enhancements. I'm still searching.