How can you tell the quality of the recording?

Does all this mean, you can like a bad recording and not like a great recording? If so, I don't get the question either. Beethoven's 9th-furtwangler - 1942, comes to mind.

Unsound,

I said 10-20 years, not 30. I agree more early CD recordings were of relatively poor quality. But I think they have improved over time as a whole. There there will always be some % that are inferior to others. That's usually the way things work.

Of course, that's by my assessment of quality. Other's assessments will differ, and few will be the same. Unless there is some objective way of measuring overall quality, good luck determining any absolute truth. Dynamics is just one aspect of a good recording. Others may have an inverse relationship with dynamics, but a tradeoff does not necessarily reduce overall quality.

Sorry about the timeline error.
It's inexcusable, there is no need for a trade off. The medium is fully capable of delivering the balance of what's there without having to sacrifice the dynamics. Classical CD's are the proof.

Unsound, you are absolutely right, that if the master tapes are dynamic, there should be no loss going to cd.

Bluesky, you answered your own question, you just listen to them. Get a few cds that are generally considered to be well recorded and mastered and then compare others to those.

If you tell us what kind of music you like we can make some recommendations. I'd guess that the new Dark Side of the Moon remaster would be an example of good sound.

Some people train their ear to do "critical listening" as opposed to listening solely for pleasure. They do this so they can note various distortions or small differences in recordings and gear. I don't think that's necessary unless you are willing to put in the effort and money to get up into the higher reaches of this hobby.

If you can get to an audio show (CES, RMAF) you can hear examples of really good sound and not so good sound. Then see how your tastes match up with others. Enjoy your listening, that's the whole point of all this.