Amp. To leave the power turned on? Or shut off after use?

[Marion]

I have a mid-80's Harman Kardon HK870 power amplifier, and was wonder if it's best to leave the power to the component on all of the time, or should I shut it down when not in use?

Someone told me it was best to leave the power on, but I'm not so sure.

Thanks!

[Kobus]

Its a personal choice, but if the minimal electricity consumption is not an issue, leave it on.

There has been other threads on this, if you want to know more you can do a search.

[Glen B]

There are two schools of thought and you will hear arguments from both camps. Some feel it best to leave one's equipment powered up 24/7 because the inrush of current that occurs each time the device is turned on, and thermal shock from cycles of heating and cooling can shorten the life of internal components.

Some persons also feel there is some sonic advantage to leaving components on all the time. There are some [front end] components like CD players and preamps that are designed to be powered all the time, and what seems like a power switch is actually a standby switch that only mutes/un-mutes the unit.

Others see no risk in turning equipment on/off as needed and don't feel it necessary to leave their components on all the time. My front-end components are designed to remain powered at all times and that is how I maintain them. Amps I turn on when needed and off when I'm done listening.

[alebonau]

my 2ch pre-pwr setup that I purchased about 6 months ago I used to leave on 24/7 and recently started switchign on and off. Really have noticed that it takes a good 20mins to half an hour for them to come in stride and start sounding as they do. So gone back to leaving them on.

My source gear (CD transport & valve DAC) I have owned for many years and those I find literally come up ot speed within minutes - its pretty much a case of switch on and go. Same with my HT AVR & multichannel amp & universal player doesn't seem to need any sort of warm up time either so I'm switching them on & off as well.

Previous to all this my 2ch pre and mono blocs I owned I used to switch on & off they used to need a bit of time to come to speed as well but jsut never bothered critically listening to them for the first 20-30mine. Anyways they have lasted well over a decade on & off and still appear fine as new.

So in a way in two minds about it all, some gear I might leave on all the time and some switch on & off.

In disc players I understand your jsut using up laser life span by leaving it on, also with any valve gear obviously your using up the tubes. Wonder if theres any component wear with 2ch pre & power amps with leaving them on all the time.

[asimov66]

i've always had my power amplifier on since i bought it.

[Crimson]

Depends. I leave source equipment (including tubed components) on most of the time. As far as amps are concerned, I do the same with the exception of a pair of Hurricane DT's that draw around 7 amps at idle (not to mention it's pretty pricey to replace 16 KT-88 output tubes).

There is always the risk, though, of a catastrophic failure somewhere in the signal chain which could destroy component(s)/speakers at best, or burn your house down. I power down all components when away from home for more than a day or two, and always unplug everything when there's a threat of a thunderstorm.

[ThomasW]

A lot of my gear runs high-bias class A/B or pure class A. So I turn the amps off when not in use.

[Ovation]

I leave my receiver on all the time because it doesn't seem to like the on/off cycle. When I turn it off/on, for about an hour (sometimes more), it makes some strange popping noises that are irritating. They don't seem electrical in nature, but rather the result of various materials of different densities that expand/contract with heat and cooling. I left the receiver on for several months (I turn it off if we're gone for three or more days) and one day it "hung up"--no functions would work (I posted a thread elsewhere on that in the Integra forum) but other than that one strange "hang up" (cured it by disconnecting the power cord) I've had no noises so long as it has remained on. But when I power it up on the odd times I do turn it off, I have several hours of random clicks and pops. So for me, the solution is to leave the unit on. Everything else I have gets turned off or goes into standby.

[fordster]

I turn all my equipment off when not in use. Most electricity comes from non renewable sources so by leaving it on it's wasting valuable resources. I personally use a Green Electricity supplier but even so I don't like to waste energy. I do notice though that, as others have remarked, it can take 20 minutes or so for it to warm and sound it's best. BTW, I'm not trying to preach at people, just saying what I do and why.

[Boombox]

As I understand it, the speakers draw "pure" power from the caps of the amp which are in turn replenished quickly. From 1st year physics, the electric field inside the capasitors are "as straight as can come", therefore very "clean" 8) . Keeping these fully charged at all times, increases the capasitor's livespan, rather than reducing it.

Long story short, my amp stays on 24/7 unless of course I go way for longer than a day...

As to the energy dissapation...well...to be honest, if all of us keep their amps on, the LED is the main energy waster....and that can a mass to quite a large amount of energy wasted collectively....I however do believe that powering on/off/on/off uses more energy than if the power would be on continuously......driving at constant velocity uses no energy (according to Newton, resultant force is zero 8) ) where as de/acceleration consumes energy .

I should ask one of our students to do the calculations......what you guys think..?? 8O

[chrispy35]

As to the energy dissapation...well...to be honest, if all of us keep their amps on, the LED is the main energy waster....and that can a mass to quite a large amount of energy wasted collectively....I however do believe that powering on/off/on/off uses more energy than if the power would be on continuously......driving at constant velocity uses no energy (according to Newton, resultant force is zero 8) ) where as de/acceleration consumes energy .

I should ask one of our students to do the calculations......what you guys think..?? 8O

An LED consumes on the order of milliwatts. Idle current measurements taken by people on other threads indicate much more idle current than accountable for by an LED.

The whole 'turning-on/off uses more current than leaving things on' statement is also a bit misleading. Consider how many times in a day you typically turn on/off your amp (and also the duration of time it takes to get to idle state) and compare that against the idle power consumption of an amp running while you're at work or catching up on beauty rest.

The car analogy is hilariously off too. If that were true, we'd only need gas to accelerate and go up hills. Sadly, we have friction everywhere to deal with (engine, transmission, wind...). Also, why do hybrid cars have engine stop/start systems to save fuel if the act of stopping/starting the gas engine when the car is at a standstill won't save fuel?

[Hdale85]

Having your TV on for 5 minuts probably burns more energy then an idle amp would if it were sitting idle for a whole day. Especially class D amps.

[Burke Strickland]

The designer/manufacturer of my power amp says it does not harm the amp to turn it on and off, and that it is designed to perform well without an extensive "warm up" period. Unfortunately, he also designed it without any way to turn it on and off remotely (no 12 volt trigger, no remote of its own).

So while I routinely click off the rest of my components (many of which go into "standby" mode instead of truly "off" off) when I'm not going to be using the system for a while, the power amp usually continues to help heat the room. If I did the energy cost calculation, I'd probably move the power amp within reach of my easy chair. :>)

However, if I am going to be gone for an extended period (longer than a day at work), I usually remember to walk over and flip the switch. But there has been more than one time that I've returned home from a trip, started to play a movie and wondered if somehow I'd blown my two main speakers, since no sound comes from them until I remember to flip the power amp back on. :>)

Burke

[Boombox]

An LED consumes on the order of milliwatts. Idle current measurements taken by people on other threads indicate much more idle current than accountable for by an LED.

The whole 'turning-on/off uses more current than leaving things on' statement is also a bit misleading. Consider how many times in a day you typically turn on/off your amp (and also the duration of time it takes to get to idle state) and compare that against the idle power consumption of an amp running while you're at work or catching up on beauty rest.

The car analogy is hilariously off too. If that were true, we'd only need gas to accelerate and go up hills. Sadly, we have friction everywhere to deal with (engine, transmission, wind...).

Agree.....it is far fetched in the real world, but without friction true...

Also, why do hybrid cars have engine stop/start systems to save fuel if the act of stopping/starting the gas engine when the car is at a standstill won't save fuel?

Well, yeh, ...saves fuel.......hhhmmm........how are the battries manufactured....??

[chrispy35]

Agree.....it is far fetched in the real world, but without friction true...

Well, yeh, ...saves fuel.......hhhmmm........how are the battries manufactured....??

Hmmm...not really, unless you turn the engine off and coast. The valves still have to go up and down, fuel has to be pumped to the engine...

Not sure what battery manufacturing has to do with minimizing fuel consumption when you're already using fuel.

[Boombox]

Ok...we are well off the point here, but before the "current" topic is banned I'll say this in conclusion.

We all are consuming energy abundantly....some more than others, but although we believe that we are doing something to preserve the environment by using "green" cars for instance, the manufaturing of some key components (e.g. batteries) are inherintly harmful to the environment and consumes huge amounts of energy to manufacture......

The world changed after quantum physics was introduced to what we know now......we need a similar break through to solve our energy crisis...!!!

[chrispy35]

Can't argue with anything in your last post there Boomer. Well said.

Are we in agreement that turning off an amp does save power? Every little bit helps...

Chris P.

[David Meek]

Are we in agreement that turning off an amp does save power?

I think we ALL will agree with that statement. Having an amp powered off does save power.

Now, whether leaving one on is preferred over cycling it. . . I don't know. I lean towards the "keeping it on reduces the heat/cool cycles which is good" camp, but I don't have any concrete evidence to support that.