How to find the good CD recordings?

Speaking of which, one wonders what role, if any, Polarity plays in the differences among CDs.

geoff, I’ll bet phase was not a major consideration for recordings of that era.
As to polarity, there would be no consistancy, don’t you think?
I should invert polarity on the flat sounding CDs.

If the various Zeppelin masters for worldwide distribution had inconsistent channel assignments, how many other mistakes were there?

@n80A small contribution fro me. I started using Tidal two years ago and have since then put huge amounts of good music and also recordings to my playlists. Thought I had it all but no no no... The recommendation for a simle Node 2 or maybe just a Sonos Connect os similar is a very good advice. You might be able to get a little better sound but also if the quality isn't good enough from the beginning its not worth it to search for better material or buy more expensive equipment. The fine with digital is that you start from a very high level compared to before (when I was young). The negative is you get a resolution that is not very friendly to bad recordings (and most are).
Since you like good old rock I would suggest you to look for recordings made 1965 - 1975. Preferably UK artists recorded in the UK. The Who live at Leeds is fantastic. The last issue of Cat Stevens Tillerman might be the most dynamic of all time. It's a little scary to listen to :-) The Doobie Brothers always top notch. Takin' it to the streets the most perfect recording i know of. You can't play that loud enough (on my ATC 150 ASL). There's lot to discover. On these recordings it feels that the technicians didn't interfere at all (or didn't know how!), they just put the music through. Nowadays, I would say you find the best sound in the Americana and Alt-country scenes. But if you are playing LZ and feel the music is flat then I must advice you to change some equipment of yours (speakers). The last issues of LZ I - III are very dynamic. A little overemphasized around 2-4 khz which could bring you some fatigue if you're listening loud, but you can feel the kick!! I also would like to thank the person that gave us Black Cat Bones - like finding a new Free record!

Thanks gosta. I'm still working out all the pros and cons of Tidal. If it is worth it to pay $20 a month ($240/year!) for the hi res stuff then it seems to me it would be imperative to have the equipment to listen to it at the highest quality level and I'm still just not sure how to do that or even if I want to spend that much more money for that additional equipment.

I might even consider the low-res subscription just to find music I like and then find good recordings of it on CD.

I'm re-listening to my earlier Zep CDs and maybe they'e not as bad as I thought. I think more volume (they way it was intended I suppose) would probably help. 

Replacing the equipment I have (which was all free) is not really an option. I'm fairly sure I cannot afford higher quality than what I already have (Aerial Acoustic 7Bs) unless I started trading and selling which is a rabbit hole I am not going down at this point since I really don't know enough to do so.

As I've been listening to my CD collection again (it has been years, only about 100 CDs) there are some standouts. I mean obvious, immediate standouts. The original release of Sting's Soul Cages is just amazing. I keep going back to it over and over. It is one of those situations where even though none of the songs on the album are my favorites, the sound is so lush and bright that I keep wanting to hear it again. The same with Pink Floyd's Animals and Wish You Were Here.

Hi again!
Yes if the record was med loud I think it needs to be listened to loud if you want to have the right feeling of it. The human hearing functions that way (the loudness curve). And I'm sure they played rather loud...
Thank you for the tip. Sting is an artist that always have a very balanced and highquality sound. Today actually I happened to find another for me unknown record when seaching around on tIdal. I thought I would have a look at the production of Lynyrd Skynyrd. And I found some live recordings that really sounded live and also with a good well-balanced sound that don't hurt your ears at higher volumes.
And - I found an acoustic record of Lynyrd "Endangered Species" that really stands out. And I mean REALLY. It's absolute top quality. In the same league as Eric C. or Nirvana MTV or Nils L. Maybe better if you prefer LS songs (I do). Why isn't this recording more well-known? Never seen any comments about it. But seen a lot of recommendations on rather dull audiophile acoustic recordings... This is what you sometimes will find exploring Tidal or similar services. And well worth 20 a month. Thanks.