Anything that has a different/better/more dynamic mastering than the CD version. Some examples: Muse: the 2nd Law Tom Petty: Wildflowers - last studio album Grateful Dead - Complete Albums Collection Blue Note Jazz Downloads
The whole classic Tom Petty & The Heartbreakers catalog, actually. They made a big deal of them all being "mastered for HD" when they were released. The Who - Live At Leeds (Deluxe)
I personally think there are better digital options for Zeppelin and Bowie catalog but the HDTracks download are decent. They are the same masterings as the most recent CD remasters.
The best album I've ever bought on HDtracks is by far the high resolution expanded version of Holland from The Beach Boys, which not only includes the original album's bonus EP in full, but restores We Got Love - a song that was only accidentally featured on some early pressings before being dropped from the final running order!
It really depends on what you are looking for in terms of sound quality. If you are looking for things that are more dynamic, then it can be rather difficult. Here are a few suggestions from the ones I personally enjoy. They may or may not be the absolute best, but I really like them. Heavy Metal: Megadeth - Thirteen and Super Collider Pantera - entire catalog Rock: Radiohead - A Moon Shaped Pool and OKNOTOK (both sound better then the CD to my ears dispite the low DR). Led Zeppelin - The first 6 albums. Better then the most recent CD remasters in my opinion.
Heart/Heart. Yea it's not as dynamic as the original CD release but it's not as harsh or hollow sounding as the original CD either. It's the remix version of certain songs and not the original vinyl mixes from the early LP pressings or original UK CD.
I think it's more interesting that despite the potential of the format, shockingly few albums have better sounding HD editions than are already available on CD. Many are much worse. That is really rather scandalous, but this market puts up with all sorts of rip offs when it comes to being sold reissues.
Some of the Beach Boys albums are good (the Kevin Gray mastered ones, mainly, but you can also get those on SACD). Bruce Springsteen - Greetings from Asbury Park, NJ. And then... Along Comes the Association A Christmas Gift For You from Phil Spector (although I prefer the old Rhino disc, this one is good also)
Do you happen to know the catalog number for Diamond Dogs or Ziggy for the W. German RCA Bowie discs?
The Clash - Sound System box set - has the 2013 remastering/hi-rez digital transfer without the ear-bleeding treble boost of the CD set. Even the cruder early single recordings sound bloody amazing! Give a listen to the sample of "Complete Control", and see if you don't agree.
I compared the downloads of both to the vinyl versions, and the vinyl masterings utterly slay the HD trax versions.
HD tracks are the best all round! So please go sell all of your old 80s cds for 50¢ each... I can recommend a buyer!