How to find the good CD recordings?


I'm new to high end audio but have a decent system. One of the things I've noticed with this new (old) system, is that some of my CDs which I used to think sounded fine just don't sound all that good anymore while some of them sound great. A lot of these CDs are 30 years old and came from CD clubs (remember those?) and typical record stores.

I've noticed in particular that some of my Led Zep CDs just sound a little flat and a little shallow while some of the Pink Floyd and Rush CDs sound quite good. 

Is this just a matter of Floyd and Rush having higher production quality from the beginning? 

Would later "remastered" Zep CDs sound better? Is "remastered" always an indication of better or superior quality? Is it just marketing hype sometimes?

Anyway, with this new system I am inclined to buy the best quality recordings of any newer music I buy and possible replace some of my old favorites.

So is there a place on the internet where one can go to get reviews of the actual recording quality and not just the music itself. I don't see iTunes or Amazon as particularly useful here. At this point I am not interested in pursuing vinyl or high end audio files. I'm still just getting my feet wet and CDs seem like a cheap way to do that.

Any assistance much appreciated,

George
n80
CD recordings matured like any medium. Take records recorded in the 30's and compare them to recordings in the late 40's and then the 50's. CD technology improved as did analog recordings. This CD bashing is way off and done for marketing to boomers on a dying hobby and a hobby which is driven by boomers. Young folks have their own way of enjoying music and that is free streaming from many sources where there is no need to buy a whole recording but a song of 2 they like. The only thing you have to stay away from is the current trend of highly compression both in Vinyl or CD or Streaming the format does not matter. Look for good mastering labels and if you like current produced music then expect not stellar sound. My experience anything from the late 90's through today sounds good as long as the mastering was done correctly. It gets down to the artist you buy and the recording was produced more than the format. I've collected music for 45 years so I have the experience in both formats and believe I sold many LP's at recorded collector shows that sounded god awful so the myth about vinyl being superior is a myth, it all gets back to the production of the recording, garbage in equals garage out.   
Regarding the LZ CDs in all their incarnations I don’t think there is a unanimous approval for any of them.

Reading all the threads on various forums you get recommendations for all of them.

The key is to find posters with preferences and systems like your own - kinda like food or movie critics.

For me, the Diament CDs are my go to; I’ve tried the 2014 remasters, didn’t care for them. Much louder, brighter/brittle; great for low level listening when the baby is asleep and you want to hear detail. For cranking? Nope - like evil gnomes with ice picks attacking my eardrums.

The Diaments are for cranking loud - for me, for my system, for my preferences.
By coincidence I found the first Led Zeppelin II LP in some thrift in MD. It’s the one with STA etched in the trailing vinyl. Anyone heard it? It’s the one they say had to be remastered due to some cartridges flying out of the groove. But it’s not the SS RL issue.
compression, EQ and bad mastering killed many CD issues of LPs.When CDs 1st arrived, most labels used EQ'd masters to make CDs from, as compared to a 1st gen master mix flat 2 track, or even a 2nd generation flat.
An EQ'd master was made in the days of vinyl to compensate for the physical limitations of vinyl.  Vinyl is really only good for 18 mins per side with decent dynamics.  When LPs became 25 mins per side and the last song was most dynamic, the mastering engineer really had to compensate.  Great ones could make compensation during songs if need be, but most stuck to changes in between songs, so as not to shock the ear.
But even then, when a US label shipped a master to the UK for local LP or CD production, it was still 2nd gen.
I was recently looking for a cut that I knew I had on at least 3 CDs.  They sounded completely different from each other.  One was a US issue and the others on later Brit collections.
A lot rests in the recording engineers hands.  Glyn Johns, Tom Dowd, the Beatles guys - Emerick, Scott, MacDonald, Smith, and others. Brilliant sound with minimal mics.
Check out Buena Vista Social Club for a truly fine recording with space and limited augmentation of sound.  Jerry Boys, old school Brit.