A final point: if you search the threads, you'll see that this subject has truly been beaten to death, as well as the more general subject of whether to turn equipment on and off or leave it on 24/7. In those threads, you'll see that repair techs and equipment manufacturers who contribute comments pretty much unanimously advocate leaving all equipment other than tube amps on 24/7 in the interests of longer component life and better sound. If you see the contrary in your owner's manual, it's for liability reasons -- the one component in a million that catches fire is going to result in a lawsuit for the manufacturer, so owner's manuals generally say "turn it off while not in use".
In response to one of the above posters, this is actually a case where the rejection of common sense and reliance upon the basic laws of physics is the way to go -- all matter, whether it is the concrete pavement of a freeway or a vacuum tube or silicon transistor in hi-fi gear, expands as it heats up and contracts as it cools down, and it is repeated expansion and contraction that compromises the physical integrity of these things over time. Keeping gear powered up keeps it at a relatively constant temperature, whereby there is little expansion and contraction -- the only downside in terms of component wear is that it can shorten cap life (capacitors are constantly being beaten by the oscillating 50 or 60 volt cycles of the electrical supply).
It is especially important to leave solid-state power amps and DAC's powered up 24/7. Naim, for example, says that it takes two days for some its amps to reach optimal operating condition (one of my dealers says "Naim amps need a week"). DAC's tend to sound like utter shit without lengthy warm-up (count on 24+ hours for most) and MUST be left on 24/7. I would add one exception to the solid-state amp rule -- Class A biased solid-state amps (e.g., Plinius or Gryphon) burn a hell of a lot of electricity and will turn the average room into a sauna if left on for long periods of time, and should be turned off when not in use as a result.
Of course you want to unplug hi-fi gear when there is an electrical storm or if you go out of town for two weeks, but for day-to-day, leave it on if you don't want it to break and if you want it to sound like the manufacturer intended.
In response to one of the above posters, this is actually a case where the rejection of common sense and reliance upon the basic laws of physics is the way to go -- all matter, whether it is the concrete pavement of a freeway or a vacuum tube or silicon transistor in hi-fi gear, expands as it heats up and contracts as it cools down, and it is repeated expansion and contraction that compromises the physical integrity of these things over time. Keeping gear powered up keeps it at a relatively constant temperature, whereby there is little expansion and contraction -- the only downside in terms of component wear is that it can shorten cap life (capacitors are constantly being beaten by the oscillating 50 or 60 volt cycles of the electrical supply).
It is especially important to leave solid-state power amps and DAC's powered up 24/7. Naim, for example, says that it takes two days for some its amps to reach optimal operating condition (one of my dealers says "Naim amps need a week"). DAC's tend to sound like utter shit without lengthy warm-up (count on 24+ hours for most) and MUST be left on 24/7. I would add one exception to the solid-state amp rule -- Class A biased solid-state amps (e.g., Plinius or Gryphon) burn a hell of a lot of electricity and will turn the average room into a sauna if left on for long periods of time, and should be turned off when not in use as a result.
Of course you want to unplug hi-fi gear when there is an electrical storm or if you go out of town for two weeks, but for day-to-day, leave it on if you don't want it to break and if you want it to sound like the manufacturer intended.