Is it best to leave gear on or to shut it off?

Does anyone have any insight on whether it is better to turn off vintage gear at night of to leave it on and never shut it off?
I would turn it off when not in use, but that is just my opinion.
For saving the environment better to turn off. I always do so.
Turn it off and save electricity.
If it's vintage gear I'm thinking you're not listening for ultra hi fidelity so a little warm up time won't bother you.
My two cents.
This is always an endless argument.

For some equipment, the cycling of power can be harder on the equipment than just running continuously.

For other equipment, such a tube amps where the output tubes have a limited lifespan, you are clearly better to turn it off when it is not in use. (A power output tube may have a life of 2000 hours when powered, whether playing music or not.) Tubes are expensive and it would be wasteful to unnecessarily replace them once or twice a year.

Still other equipment doesn't even really turn off when its off. These are generally low power consumption devices, but the only way to turn off a Slim Devices Squeezebox, for example, is to unplug it. Any device that uses an external transformer will use some power as long as the transformer is plugged into a live circuit.

Heat is a big enemy of electronics. If your device generates much heat, then it'd be good to turn it off. Another advantage of turning equipment off is it reduces (but does not eliminate) exposure to power line surges. Weigh that against the stress on/off cycling places on a unit.

Take a look at your system in that light and then do what makes sense to you, keeping in mind that no piece of electronics will last forever. From an energy saving standpoint, some devices use a lot when they are on (e.g. tube amps) while other devices are very low power consumption and may not even turn off. Again, examine your system and go from there.
your gear will always sound better warmed your preamp and amps i would leave on all day then turn them off at night
Turn vintage off completely. Digital should stay on 24/7.
Some gear has no on/off. My Pass preamp is one such - to turn unit off, pull plug. My amp I keep in Standby. My digital stuff draws about 10W a box; it stays on for convenience's sake. I turn thr transport off. My phono stage is like the preamp: plug in; it's on. That's just me though.
cheers apo
Tubes turn off, SS leave on.
I once had my first-ever ''high end'' unit, the diminutive original Naim Nait, a whopping 18 watts per channel, but sounded subjectively like an 60 watter. Turned it on in 1984, turned it off when I sold it ten years later in 1994 ! We are are almost 2008, and the guy I sold the unit to, a friend of mine, still has it turned-on to this day! We are talking 24 years here with only a 1-hour interruption !

Quality gear can usually take it, and some manufacturers, like Naim - actually recommends leaving amps ON at all times, including sources.

When I think of all the expensive gear I have owned since, including mega-dollar tube amps, and factor in the hours wasted chasing for the Holy Grail of sound, I sometimes miss that little red light in my living room, confirming that my tiny amp was on constant warmed-up-and-ready mode.

anything with a microprocessor in it should be disconnected from your power source or at least put in standby; you would never want your computer to deal with a brown out and stereo equipment these days is unfortunately very sensitive to dust, heat, cold, power deviations, and lunar and solar influences (okay, not those!). never leave a cd in your player- a power interruption will cause major havoc, even lock-up, if the cdp tries to figure out what to do with the disc. saving electricity is a very good idea as your power company may be contributing to environmental degradation. OTOH, DACS AND PREAMPS usually benefit from staying on all the time. this is a great argument for an all-analog stereo system come to think of it...
Here we go once again. NOT ONCE has anyone cited scientifically that powering well made equipment up and down causes damage or degrades performance. Plus, all equiment is more vulnerable to damage powered up but unattended.

Yeah, sure it needs a little warm up, that's normal, but much can be accomplished in 20 minutes. ;-)

Save energy and your sanity. If you aren't listening to it, turn it off.
On all the time, get a Hybrid car and recycle if you feel guilty.......but if it is SS or even a tube pre I leave everything on 24/7. My gear isnt exactly vintage but isnt new either, I only shut off if out of town or in Thunder Storms.
I don't think it's a question of vintage vs. modern, but solid state vs. tube.

I kept my Bryston amp and pre-amp on almost 25-years and it sounded great all the time. I wouldn't do that with tube equipment, since there's more likelyhood of a tube failure and the lives of tubes are relatively short.

I'm turning off my Conrad Johnson solid state control amp after listening. It's got a couple of LED displays and some switching features that worry me. The Bryston pre-amp was passive and the amp didn't even have a power switch.

Generally I think it's a personal decision.

Hi Mlsstl. Thanks for the very helpful response. I found that there are many answers. I also found out that tubes might be right for me. The amount of time my system is on I would be going through about two sets of tubes per year.
All great equipment stays on in stand-by mode. Keeps the transistors ready. Solid State not familier with tubes but I love high doller tube systems.