Oh boy were to start this discussion.
This always turns out to be an emotional discussion instead of a technical one.
So I will try to separate both.
The emotional side is the simplest one. The perfect sound is the one you like and it will have nothing to do with how the sound source was made. So philosophically speaking the perfect sound is always the one you like. Your perfect sound wil not be my perfect sound.
The technical part of it is more complicated due to how much it has been studied in the last half a century.
It will have to take into account the model used to convert sound into 1010101.
Now these models are hard to comprehend. I can’t fully grasp them, but being in the analytical field I understand modeling.
Most models will grab the information given, source, and straighten the curve to make it easier to store it in less data, saving space and effort. MP3 being the most compressed. Now are these models cutting the sound or mixing it in the upper and lower levels to flatten the curve? the same way we use an EQ? because its essentially the same thing.
I am into quads and much has been talked about the modeling use to separate these channels L/R F/B. The idea doesn’t differ that much.
So the most information that can be recorded from the original master the better. So CD's are great as long as the source and the technical recordings were good and what you play them on are also, but is it better than records, some say no, but then again you need a good set up to play them.
So which of the 3 discussed models are better? Keeping the source the same and the models used are good, the bigger format which is a CD is the best, Does it make a difference to most of us humans, probably not.
But for us humans its all in the way its perceived by each individual. so at the end of the day the perfect sound is the one you like.