One of the interesting quirks of listening to old LPs that were originally mixed for vinyl is how different successive LPs by the same artists can sound. Here are two examples:

Steely Dan "Katy Lied" and "The Royal Scam"
"Katy Lied" was recorded in 1974, and Steely Dan went to great lengths to ensure that it was a state-of-the-art recording. The success of "Pretzel Logic" had given Donald Fagen and Walter Becker more leeway with recording, and they used it to not only equip themselves with more recording hardware, but they also purchased a brand new Bosendorfer grand piano for the recording.
However, when it came to mixdown time, trouble struck. The decision had been made to use DBx noise reduction, and this caused all manner of problems, chronicled here by Denny Dias. Eventually the LP was successfully mastered, but relics of the compromises forced in the mixdown can be heard in the overall sound. Despite the tremendous basic sound quality, both in terms of depth and warmth, the most notable defect is clipping and phasing of the cymbals, notable on "Your Gold Teeth II". However, I still find the sound quality of the LP to be tremendous, and the remastered LP on "Citizen Steely Dan" sounds wonderful.
"The Royal Scam", by contrast, has a sound that I find unattractive, particularly in the drums. Also, the lead guitar sounds (mostly played by Larry Carlton) are harsh and pseudo-metallic without being convincing. Carlton's lead parts on "Don't Take Me Alive", for example, sound like somebody with a cheap amp and an effects pedal trying to sound nasty. Coupled with dead drums that sound almost like cardboard boxes, the overall soundscape is leaden and lifeless.

Weather Report "Night Passage" and "Weather Report"
This time the sound issue and time sequence is reversed. Most of "Night Passage" was recorded in the Summer of 1980 at The Complex in Los Angeles, a new studio managed by George Massenberg. The band recorded most of the basic tracks live in front of an invited audience (audience bleed-through can be heard at several points in "Dream Clock" and "Port Of Entry"). The title track was a non-live track. "Madagascar" was a live recording, recorded live in Japan in 1980 by Brian Risner to two-track.
However, despite this being one of the great Weather Report LPs, the sound is anything but. It sounds largely dull and lifeless. The contrast with preceding LPs is stark and unflattering. I bought the CD copy of "Night Passage" in the early 90's, but the sound quality is no better than my original vinyl copy. As far as I know, this LP has never been properly remastered for CD.
The following year's LP, "Weather Report", despite being a pale shadow of "Night Passage", has a sound quality as great as "Night Passage" was poor. The sound leaps out of the speakers, and is crystal clear and crisp. Different recording studios may have played their part, but there has to be something else to create a plausible explanation. I would rather have had the sound quality reversed, with the better sound quality on "Night Passage", which is still one of my favorite Weather Report recordings.
More recently, several tunes recorded at The Complex concerts but presumably not deemed good enough at the time appeared on the Weather Report CD compilation "Live and Unreleased". The sound quality of these tunes seems to be very good, far superior to the original version of "Night Passage", which suggests that the mixing and/or mastering process might have been responsible for the dead sound on "Night Passage" itself.