Even though I do live in a residential neighborhood, where one might assume that the power is rather clean, I noticed that my system's performance typically got better around 11PM at night. I could not figure out whether it was my neighbour's overdone christmas lighting, or someone's heatpump/AC system, or a change in the power grid.
Most likely, I could not have changed those underlying conditions anyhow, so after experimenting with some Tripplite computer grade line conditioners, which helped somewhat, I got a loaner Chang litespeed 3200 from my dealer. That made a noticable difference in particular in the CD player, which sounded let me say "cleaner" for lack of better words.

I found that difference noticable enough to order a Chang Litespeed 6400 power conditioner, which arrived yesterday. As opposed to the 3200 the 6400 has two digital outs, which are also supposed to be "fully filtered", and the analog outpuits are triple filtered. I am using one of the digital outputs for the CD.

Contrary to Chang's instruction manual, I am using the other digital out for the tubed pre-amp, and I plugged the power-amp into one of the analog outputs.

Whoa !

The best way to describe the changes would be to say that everything is a bit clearer and cleaner now. Most pronounced sonic improvements appear in the bass, which seems to extend just a little bit lower, and is better resolved. There also seems to be a certain "calmness" in the system, it now sounds seven better than at it's best before, and all the time, so it is truely 11 now anytime...