Inna, I have a Pass Labs XA30.8 amp and a Pass Labs XP-20 preamp. They are great. The amp is a bit heavy 100 lbs, being class A it puts out a little heat. I don’t run my amp 24/7. 1 hr warmup is all that’s required for excellent sonics. I have no negatives for the Pass Labs XP-20. As with all equipment I would say ~ 500 hrs breakin to hear the “real deal”
