One other thing about the service and modification of Krell FBP 350Mc. 5 op-amps in each monoblock was replaced with new and better ones.
In one monoblock there was one that did not measured as the others. The bias control was a bit off in one monoblock All of them in both were replaced with the new ones.
My knowledge about these specific component and their effect on sound are not much.
What is it to expect about the performance and sound from new Op-amps compared to old ones.
Witch components generally degenerate with age and witch components keep their performance during a long time.
The obvious easy answer is that electrolytic capacitor are degenerating during time. Some more components?