With the Adcom ACE 515 line enhancer. It has outlets for power amps and other outlets for other components. The turn on of the power amp outlets is delayed 10 seconds on startup to allow the preamp and other components to power up and stabilize first. When I switch off the adcom after I'm done with the system, it turns off the power amps first and gives them 15 seconds to power down before switching the AC off to the other components.

I do leave my uverse receivers always plugged into a live outlet, as well as my TV's. I also have a purely two channel non digital preamp, a Threshold T2, hooked into my main system that has been powered up continously for about 14 years since I bought it. I use it's remote to put it in standby when I'm not using it, but it has a separate 10 pound box sitting next to the main unit on the shelf that is it's power supply section. It's pilot light is always on.

According to Threshold, that preamp sounds best when it's circuits are kept active all the time.

Scott