Remasters - are they better? What exactly is it?


What exactly is the process to remaster.  Not the FULL 10 page answer but just in general.  What is being tweaked?  Why can't I hear a bigger difference?  Old recordings (through Tidal) seem to sound essentially the same as the original.  But I've also not done an exhaustive a/b test either.

Anyway, do you skip the "Remastered" titles or seek them out?
dtximages
Not wanting to start a fight or anything Blu Ray discs oft suffer the same aggressive dynamic range compression as any other digital format, including CD, hi res downloads, SACD, whatever. Check it out on the Dynamic Range Database.

http://dr.loudness-war.info/album/list?artist=Beatles+&album=Abbey+Road
I have noticed though, that when I buy the original version, it turns out that the remaster was better. Whenever I buy the remaster, it turns out the original was better. 

….hmmm....
I have been going through a collection of 767 CD’s and SACD’s, about 400 of which are pop/rock from the Sixties onward. I am ripping them using dBpoweramp and checking their dynamic range using the TT-DR Offline freeware. The discs are listed in a spreadsheet sorted by artist, original release date, and the release date of the specific disc.
It will come as no surprise that there is a definite falloff in DR--i.e., increased compression--from the mid-1990s onward, as titles were remastered and reissued. This trend is associated with an increase in the proportion of tracks that clip. It includes some artists usually thought of as exemplars of quality recording. Dire Straits/Mark Knopfler started out as high as DR15 but declined to as low as 7. Bruce Hornsby went from 13 to 6; Norah Jones from 14 to 10; Sarah McLachlan from 13 to 8; Joni Mitchell from 14 to 8; Steely Dan/Donald Fagen from 13 to 9; and Sting from 15 to 7.
It has been interesting to find that some of my favorite albums are fairly highly compressed. To me, this demonstrates that the music rules, but also that compression is seductive and I am not immune to its charms. I compare it to the way that electronics stores max out the brightness of TVs and computer displays because it impresses customers. A highly compressed disc similarly "impresses" with its big bass and bright midrange. It’s fun to hear more detail than in the past, not stopping to question whether the heightened midrange is in proper balance with the rest of the music, or swamps the vocals.

It’s when I do comparisons with less-compressed discs produced from about 1984 to 1995 that I understand the price to be paid. The highly-compressed disc, assaulting the ears with relentless loudness and a measure of distortion from clipping, gets old fast. It is like listening to TV commercials all the time. The older disc is less "impressive" and may need to be turned up to be fully enjoyed (the good news being that it is less likely to clip if turned up), but it often sustains my interest much better.
Over the last twenty years or so a lot of pop/rock music has increasingly been mastered for play on car stereos, mobile devices, and earbuds. Those of us who insist on listening to music on a quality system are probably now in the minority. Whether you like remastered titles may depend on how you plan to listen to them.
@ivan_nosnibor 

Research on Hoffman forum and DR DB helps make the right buying decisions. Bad side of this is when research tells you the best recording is that one on Discogs going for $100 (but sometimes cheaper on eBay if you can trust the seller).
In my opinion, many here have hit on it.  Much of what was recorded back in day, as far as popular music, was recorded where much of the highs and specially the lows, were rolled off, because in general most buyers didn’t have the capacity to reproduce the sounds rolled off, so why put them on the recording.  If the master tapes have the content, then the remaster process can add, what was not on the original commercial recording.
As some said, Desperado and Crime Of The Century are indeed quality recordings made back in the day.  Classical music, as well as some jazz, didn’t suffer from engineers rolling off the frequencies, in most cases.