Higher resolution Jazz

Actually, you'll need to judge for yourself. Many people think old recordings still sound great, and even prefer them.

Most jazz recordings since the hifi era that started in teh late 50's, including those in mono, are pretty good quality I think. I enjoy most modern digital remasters of a lot of even older material these days. They are what they are soundwise and though often lacking technically from a hifi perspective, are heirlooms of a prior age that was different and should just be enjoyed for what they are, lots of good often fun music made by a lot of talented individuals that were recorded as well as the technology of the time permitted. Some digital remasters of even very old stuff from the 30s and 40s can sound surprisingly good, though few would be your typical audiophile fare. It all depends on what you find interesting that matters.

Hmmm, I'll give some more older recordings a listen again.

My friend... there is a German Label called Nagel Heyer. This label has 100 or so offerings of absolutely stunningly great music that is really, really well recorded. There are some audiophile labels like Mapleshade and Chesky that has recorded largely 3rd/4th tier jazz (mostly really weak music) that is recorded well. But Nagel Hayer is 1st tier awesome jazz recorded wonderfully. You cannot go wrong!