The sad thing is that most everyone who has posted hasn't a clue about mastering and the art of it.
Ford A. Thaxton
Since when did producing CD releases from low quality MP3s become an art? What school must I attend to take historical and legendary recordings, and compress the crap out of the dynamics and dull the sound quality just so I can't slap a "remastered from DSD" sticker on it? When did it become a skill to release and SACD thats sourced from and older 44.1 PCM release and sell it at a premium price become respectful? What have you demonstrated that you actually know here?.
I know many mastering engineers and NOT ONE prepares a CD from crap 320KBPS MP3s. Sorry doesn't happen.
Brickwalling happens, yes. Over-EQing happens. Most SACDs I have worked on or with others on are taken from pristine sources. 44.1 masters are common. The key is whether it's in 24 bits or 16. Remember the ones that are most likely were RECORDED in that fashion. To upstream it above the 16/44.1 goes beyond what most engineers I know would do.
I know many mastering engineers and NOT ONE prepares a CD from crap 320KBPS MP3s. Sorry doesn't happen.
Several CDs have come out in the past few years that were sourced from MP3. The Silvestri G.I. Joe score, for one film music example, but also the Deluxe Edition of Beck's Odelay, where certain tracks from the bonus disc were sourced from MP3s, even though they were readily available on CD singles, at the very least.