Leaving my amplifier on ok?

 Electronic components don't wear out like for example mechanical components. But a mains voltage spike or lightning strike - that'll fry your amp and perhaps other components - nicely. Maybe unplug your system if you're not using it for long periods.

@bishop148 

Electrolytic capacitors and relays definitely have a life expectancy, so there are components in audio equipment that need to be replaced.

Dam! Don't you hate being wrong!

However out here in the boonies, lightning strikes are frequent and without a very fast over voltage protection it can and will damage your gear.

I have left my Class D amps turned on for years. 

@bishop148  Try an isolation transformer. Not only does it protect your equipment, but it improves the sound more than a high end power cable.

@invalid  It's heat that's the main enemy. If the caps don't get hot, they'll last and last.