I would caution you, however, that making this kind of comparison is dangerous at best. You must presume that the two recordings you are comparing come from the same master and the engineer made the two pressings identical when played back through the same monitor. You are aware that many CD's are engineered to sound good on cheap consumer electronics and automobile systems. Of course, you have no bias as to the expected outcome and your system properly handles any pre-emphasis on either recording.

I don't know. You may well be right. I don't have a horse in this race.

The best improvement you have made to your system was the last tweak installed. The best improvement you will make in the future is removing that tweak.

Bob