Good power cord for Rotel?

Did you already do the source? That's the place to start.

Didn't swap out the CD or preamp cords yet -- I was told the big difference would be in the amp, not the source. I tried out a Richard Gray 400 Pro that had NO effect, so I'm a little leery about tweaks.

I don't mean to look down on your system (it's very nice for the money it cost);.... however;.... in my experience Rotel while really great stuff for the money it costs, is not really refined enough to notice any big changes from tweeks of any kind. Maybe a little....

So for that reason, I am not surprised at all that you did not notice any improvement from adding a Gray 400. The same will go for power cords. Get some hospital grade 14 awg cords to replace the 18 awg cord that came with the units. You will be fine. You will likely find them at your local electrical supply store for $10 to $20.

If you have a decent television, plug that TV into the Gray and the picture will shine...

Sugarbrie -- No offense taken! I tried it on a VAC preamp and Audio Research VT-100, with no noticeable effect. Also tried it on my video (Loewe Calida -- not exactly a Magnavox) and the picture did not change. Don't think I'm deaf AND blind, but . . .

Try PS Audio extreme Statement cords. They work equally as well on CD and amps. Generally they reduce noise and add a bit of weight to the sound.