(1) Yes to always leave it on (for solid state only). I used to turn everything off, but my trusted dealer convinced me otherwise & he is absolutely right! I always noticed improvement in systems' sound >1 or 2 hours on, but it's not at best until about 30 hours warmup. Dlr. also says the equipment will also last longer (eliminates thermal cycling). I do pull the plug during thunderstorms of course, which leads to your first question. (2) Power-strip type conditioner (again dealer recommended) is the Chang Lightspeed (Stereophile recommended also). There are several models & pricepoints. Unlink many conditioners, the Changs do not constrain current peaks. They also have integral MOV transient protection, for those nasty lightning strikes (but I still power down during a nearby storm, if I'm home at the time - why live dangerously?). I have a Chang 3200 for the lower current devices, & or smaller amps if you have that. But my SS amps run 100 watts/ch to 150 w/ch (I have some different ones that I change around sometimes) so for that I got the Chang 9900 high-current conditioner. Still use upgrade power cords on everythng too, but much filtering (like a heavy filtered cord plugged into the Chang) constrained dynamics & rolled off the highs & lows. Example: the McCormack DNA-1 amp works better for me with a Custom Power Top Gun HCFI heavy-filtered cord plugged directly into dedicated AC line. But with my Ayre V-3 bi-amp setup, I use the Synergistic Research Designers Reference2 AC cords plugged into the "Chang 9900Amp" filter box. You must experiment with your rig for best results; try many different combo's to find what you like. Good luck & happy listening!
