In reply to:
Is there any harm to leaving a system (amp,pre,cd) powered up at all times, other than the electrical cost?
Absolutely!
The harm created by electrical generating stations floods upland areas increasing methyl mercury levels in fish and inevitably in human consumers.
An increase in electrical usage requires more load on coal and oil burning plants adding tons of carcingoenic PAHs into the atmosphere along with NOx and H2S which forms the lovely smog and acid rain that falls in our fair countries.
More electrical usage means more nuclear plants and an increased production of spent, yet highly radioactive uranium (or plutonium) rods.
Do the earth a favour and shut off the electronics. Don't listen to the fear mongers about home electronics 'life span'. It is bunk.
Ask anyone who has owned x unit since 1970/ 1982/ 198....and still uses it.
