The problem is that the original master tapes have often vanished... search Google for Billboard's articles about the state of major recording labels' artchives. Frequently a second, third or fourth generation safety master has been used, or the record has even been mastered from CD or a vinyl copy.
Even when the tapes have survived, they have frequently been stored improperly and deteriorated.
Add to this that records in the '50s and '60s were mastered using all tube equipment in state of the art facilities... since the '80s, nobody is making new cutting lathes.
Older mastering engineers were artists who learned to cut vinyl in real time, varying the EQ themselves by hand (you can't make a mistake or you have to start all over again), while today it's done by computer (this is the use of the digital delay... in the old days it was done by a Studer-type machine with a second head).
It's possible to do good vinyl reissues, but few people succeed. Just do an A-B with an original pressing of any of the recent Analogue Productions, Classic or Speaker's Corner pressings. They are mostly far inferior. One notable exception is the Mercury Bach Cello Suites with Janos Starker.
Good luck
Patrick
Even when the tapes have survived, they have frequently been stored improperly and deteriorated.
Add to this that records in the '50s and '60s were mastered using all tube equipment in state of the art facilities... since the '80s, nobody is making new cutting lathes.
Older mastering engineers were artists who learned to cut vinyl in real time, varying the EQ themselves by hand (you can't make a mistake or you have to start all over again), while today it's done by computer (this is the use of the digital delay... in the old days it was done by a Studer-type machine with a second head).
It's possible to do good vinyl reissues, but few people succeed. Just do an A-B with an original pressing of any of the recent Analogue Productions, Classic or Speaker's Corner pressings. They are mostly far inferior. One notable exception is the Mercury Bach Cello Suites with Janos Starker.
Good luck
Patrick