Do you always keep the Amplifier powered on

Well , it may depend on where you live .
I live in the lightening capital of the country !
I have , so far , lost a microwave oven , television and a heat pump compressor to lightening strikes !

Good luck .

When I had my Simaudio i7 integrated I left it on all the time, but on standby when not playing. This is strongly suggested by Simaudio.
"The Standby button disengages the input section from the rest of the i7's circuitry and turns off the digital display. However , when in Standby mode all audio circuitry remains powered up to help maintain optimum performance." (from the Simaudio manual)

All due respect to Schubert, but you don't turn off your refrigerator when you leave the house. I have been an appliance service technician for thirty six years and have seen appliances that came very close to starting a fire but haven't.
I would not be apprehensive of leaving the amp on. Whatever you are comfortable with.

Yes, I do leave it turned on (tube amps, no). I read somewhere that turning your amp on and off is actually harder on the equipment than just leaving it on all the time. I'm sure there are other items around the house that we leave on all the time. Clocks come to mind...

It's kind of funny to hear you guys break down the cost ($20-$30 per year) when you probably have $500 speaker cables... Yes, I'd like a super sized big mac combo with a diet coke please, I'm watching my weight ;)

Hi Mtrot, what amp breaker are you useing on your krell 400cx?, do you have a dedicated line for your amp?, I can help you here if you answer, may be able to get your amp to run alot cooler and smoother, more dynamic, speed, etc...