If youre not blowing fuses and all seems well, all probably is well. But if youre itching to do something, I know people who swear by the improvement they realize by regularly cleaning and polishing contacts (PC, IC and tube). FYI, cj offers a renew" service for their older models, but unless you feel that somethings wrong, Id wait another ten years before I explored that option. Ive always been happy with cjs advise when Ive called.
Maintenance for Tube Preamps
I've enjoyed my Conrad Johnson tube preamp for a decade or so. Other than replacing the tubes a few times over the years there hasn't been anything else done to it. Are there other maintenance tasks that I should attend to? I believe all the capacitors are polypropylene (no pesky electrolytics!). All seems well, but I want to make sure I'm treating it properly.