I went through these.
The 24 bit 44.1k editions being offered on HDTracks are in fact the exact copies of these tracks that were prepared for the CD editions with the extra peak limiting and boosting, high end eq bump, and added noise reduction. Just the already prepared files but before the reduction to 16 bit.
There is absolutely no content left in these versions of the mastering that was lost in the 16 bit reduction but is still preserved in these 24 bit copies. The "mastering for portable device listening" (eg. iThings, phones) work eclipses anything to do with SD vs. HD formats.
Perhaps the intention was something else? That these versions are being offered in 24 bit suggests they might be the unmolested master edition like the Creation sampler. They are in fact the very same edition as the CD's. You can even null the 24 bit files against the 16 bit files and hear silence! (You'll see a little wiggle on the meter down at -70db.)
If these were never meant to be a more deluxe HD version and instead an alternate budget edition, well there you go. These are NOT the HD edition like the Creation sampler tracks.
In defense of these "mastered for portable devices" editions (as I'm calling them), Pink Floyd have MUCH higher standards than most others out there! Really truly. Some of the tracks were not altered very much at all from the masters. Some sound like absolutely no difference. But a few as discussed before have added noise reduction, brighter eq, and are louder. Just be aware that these 24/44.1 copies have the exact same processing done (whatever you think of that).
Listen to The Violent Sequence for a more obvious example.
Let me be VERY clear that this set sounds head and shoulders above a lot of what gets released in the wild! (With the exception of the 3 remixes that were blinded with high end eq!) I do apologize for jumping in the deep end and not making that point clear enough right up front!
Just that if you were looking for a deluxe HD master version - these HDTracks versions are not it! They also omit ALL the bluray content which is not trivial.
Buy the box and the Creation sampler and continue being patient.
Today's cash register analogy:
A till with only bill slots and no change bins is your mp3.
A till with change bins that go two places to the right of the decimal is your CD.
HD formats can go further to the right of the decimal. (And it's true that this only matters sometimes.)
If you can't afford no shoes, none of this will help you! (Cue Frank Zappa)