Turning off equipment...Should there be and order.

[wes]

This is a question for anyone...

I heard that when turning on the gear, preamp should be turned on first, then power amp... And when turning off...it's power amp, then preamp.......Does anyone know why it should be like this? What kind of damage will happen if the opposite is done?

Steve?... Gary?... Sckott?... Pigmode? Grant?.. Jim? Audiogirl?............
Anyone wanna comment?...............

[Gary]

I recall something about this a long loong looong time ago. I'd like to know the answer, too.

I think what I vaguely remember is that it had something to do with the speaker thump (when they first get power). For example I have two amplifiers in my house system. The HK has a time delay protection circuit in it where it'll take 10 seconds to "warm up?" and then music can be heard. The NAD amp does not have this circuit, probably since it was designed to go with a NAD preamp. Immediate music. Speaker thump.

Either that or the 20 year old NAD needs fixin! :D

This is all SS stuff, of course. I don't think tubes have this type of problem.

But I believe that there IS a proper way to turn on your system. Anyone know?

[wes]

Hi Gary,

It must not be too much of an issue than I guess, because I haven't heard any horror stories.........

When I was having problems with my tubes I called up the guy that I bought the amps from to ask him what the dealio was..
He suspected it was my ss phase linear preamp(blowin fuses in the amps)..........He said. "Always turn on Preamp first, and when you go to turn it off, preamp last."...........He thought that my Phase linear was the culprit, but it really was just a flaky pair of Chinese firecracker rectifiers that needed to be put up for beebee gun target practice.............That was pretty fun........:p but that's beside the point:rolleyes:

-Wes

[Dave]

Wes and Gary,

I've heard that the reason behind turning off the power amp first is to in fact avoid the thump of sudden capacitor discharge and when you turn on your pre-amp first it's to give the power a correct direct path to follow as opposed to the power having nowhere to go when turning on the power amp first.

I don't know how factual it all is but that's what I do as well.;)

[wes]

I never thought that the amps power would go to the preamp. I figured it could only power the speakers....................but I'm not a techy....

-Wes

[Dave]

Wes,

Think of it this way.

If there is no path to draw what it needs ie. power amp. You create sort of an electronic vacumn, sort of like if you put your hand in front of the air-flow on a vacumn cleaner.;)

[Grant]

I leave the amp on all the time and turn everything else off.

[Dave]

Wes,

Are you running tubes or SS?

If it's tubes I would follow Grants lead, even though I do anyways as my SS system only gets completely shut down when I'm going to be gone for more than 24hrs. or during an electrical storm.

Despite the lack of tubes, unbeknownst to most (spelling?), SS systems require some time to "warm up" just like their tubular cousins.

[Andy]

I never shut my stuff off.

[indy mike]

I keep my stuff on 24 hours a day; if I have to shut down I shut off my Dynaco ST-150 amp first - if I'm turning things on the amp comes on first, then I wait a few seconds to let the filter caps get charged up so I avoid a big old turn on thump...

[wes]

I have tubes..............I don't really feel comfortable leaving my Dynaco Mark III's on longer than 10 hours a day. Plus it wastes tube life and it gets so fricken hot. It could be a fire hazard.......


-Wes

[Douglas]

I was told by someone who I guess I trusted to turn off the ADAT first, then turn off the mixer which is what I've done ever since. I imagine that might work the same way with a component and a receiver or amp.