Leave it on?

I feel it is up to each individual to decide what they feel comfortable with.   I have a streamer which stays on all the time (I restart it periodically as it is a computer after all). My Transport stays on all the time... My DAC stays on all the time and is periodically restarted.   I have  a tube preamp that is only powered up when used and a pair of Pass labs amps that go into standby when not being used.    I do substitute in a pair of Quicksilver tube monoblocks that are only powered up when playing music.     I try to use common sense in what I leave on 24/7.   I do not mind a short warm up period.....

I even leave the computer on.

@jomace 

Why not (as it’s on) ask the computer what it thinks is best practice?

@mylogic 

Your logic is flawed at best. 
“How confident are you leaving other appliances on all day and night?”. 
Do you turn your fridge off at night?  Leaving a DAC on with the display off won’t affect global warming in a million years. There is no work done and the energy consumption is negligible. Comparing this to a car engine in idle state is ridiculous. The engine is doing serious work so much so that the fan will come on after a certain time to cool it off. The engine is still running even at idle. 
You are fast to call people ignorant and unconcerned about the environment but your logic doesn’t make sense. Why would a manufacturer give you advice that will be detrimental to the longevity of your equipment and expect that you will buy another one from him after the first one fails? Do you have the stats on the number of fires started by hi-fi equipment left on continually?

you should try to express your opinion without throwing insults around like you are a nine year old. 

@spenav 

Have you not heard of the butterfly effect? If not look it up, research it a little. Lots of little things all mount up.

Refrigerators are required to be left on, a fact of life.

The car example was an ironic comparison to make people think. I see it worked on you. It was not like your car engine “doing serious work” It was not meant to be taken seriously.

Manufacturers want you to buy more of the same, it’s called sales marketing and supply and demand. Some manufacturers intentionally build in operational redundancy (like mobile phones), but that’s another subject.

l will ask my stepson about equipment related fires in the UK. He is a chief fire officer Commander for the new Hinckley Point 2 Nuclear Power Station under construction, and the Trident submarines laid up in Plymouth over here in the UK. Will that do? 

It should not be considered a swear word to use stupid, ignorant or the like and l do not address these to any individuals. I’m sorry if you may possibly find my “handle” mylogic in anyway confrontational, but if you do l suggest you are maybe the child here.

My opinions are mine alone and in my opinion only based only on what l believe.