To make matters more complicated, different recordings of the various classical pieces are better than others. If you read the NPR Guide or the British one (Penguin maybe?), they will list specific recordings with conductor and orchestra. I have three different versions of the Brandenburg Concertos and they are all different.
Often when classical recordings are reviewed, they rate both the performance and the recording quality. I appreciate that. I started building my classical collection from the bargain bins but now I seek out one of the better versions of a given piece.
A good free resource is the ratings on
Arkiv Music, a retailer of classical discs.
Jim