Musical Fidelity A220 integrated amp

I have a 12 year old musical fidelity integrated amp which I leave on all the time. It draws 36 watts on standby. My understanding is that the capacitors, which Are most likely to fail, are stressed the most from being turned off and on as opposed to simply being left on. I can’t say I’ve noticed any difference soundwise from when I first turn it on or when I leave it on, but that’s the story at my end. 
 

I’m sorry. That’s what I meant. When it is on but no signal is being sent through it, mine drives 36 W. It’s a 150 W amp, so I’m imagining that yours draws less. At one point, I did the math and decided not to worry about the small addition to my electric bill. Honestly, it seemed about as good to do it either way.