OFF, Standby, or ON for amplifiers


I know that it is best to keep most digital gear "ON" all the time but how about amplifiers. I have been under the impression that if you never power down there is less stress on the equipment and promotes longer life. Is this true or am I way off? Thanks in advance...John
jla
Except with tube amps. Since their life is so short, you'll be going through a new set of tubes every few months. So leave them off when you are not listening.
To chime in: I have a Moscode 600. It sounds realy low fi unless it has been "on" for at least 8 hrs.It is the slowest to warm up amp I know of.(mosfets & tubes)
FWIW, I have always left my solid state amps turned on, and just recently had to do the first repair EVER on an amp I have owned for nearly 10 years. I currently have a Bryston 4B-ST, and I leave it on except when I away for extended periods, or when there is an electrical storm in the area.
Another perspective on this question can be found at amp designer David Belles' site "www.powermodules.com" (click on "articles" on the home page.) In the short article he states that both passive and active components can be subject to shortened life if the component is left on all the time. He feels that the best compromise is to turn the unit on a bit before the listening session to let it warm up.
As usual,the answer depends on the conditions;if the equipment in question get real hot under usage,( the first thing that comes to my mind i a class A poweramplifier),then there is several thing that happens inside it. When turning it on,the heat that is built up causes tiny movments in components,solder joints,etc,which with time can cause problems.On the other hand, as David Belles rightly states,leaving the amp on, can cause electro- lytic capacitors to dry out, but on the other hand,the same capacitors are prone to deteriomental chemical changes, when they don´t have a voltage over them. I think;that the cooler things run,the wiser it is to leave them on all the time.Of course there is also an environmental aspect to it, I´m a bit scepical to big con- ventional class A amps. They are very ineffective! If You use this type of gear, a compromise could be to install a resistor (high wattage type) in series with the line rails and a by-pass switch over the resistor,don´t do this if You aren´t competent enough, though.Doing this is only meaningful if Your amp doesn´t have a stand-by mode.And it can be more or less meaningful even if there isn´t a stand-by switch, and that depends on the construction, and particulary the use of voltage stabilization.