Leaving Amps on 24/7

cooky560

Standard Member
I was talking to a few friends of mine, as well as reading various posts on the internet, and they have said that it's a good idea to leave amplifiers on 24/7 because it vastly improves the sound quality, since my amplifier is in a closet (the wires go through the wall to the room) this would also benefit for convience. I am not greatly worried about the increase in energy usage.

My question is, is this true, can I leave my amplifier running 24/7? and will there be any benefit?
 

Badger0-0

Distinguished Member
Welcome to the forums :thumbsup:

Well, I very often leave mine running 24/7, mainly because I usually forget to turn it off :oops:

I disagree that it improves sound quality, but can see what your friends mean, in that amps take a short while to warm up.

Downside is semiconductors have a finite life and you may well be wearing them out quicker.
Good side is you aren't switching relays all the time.

Swings and roundabouts, I guess.
 

Mrhappy37

Member
Hi, I find the amps benefit greatly from being left on 24/7. Infact if I switch mine off they take a couple of days to sound up to what they did prior to switch off. According to Naim Audio you are more likley to wear out your amps by switching on and off as this is when the circuits are most under strain.
Kind Regards,
Clyde.
 

dazza74

Distinguished Member
It's good for the environment as well :eek:

when you refer to 24/7 are we talking on standby or literally on all the time?
 

Alan Mac

Well-known Member
In the nineteen-fifties and ‘sixties we had valve test equipment (such as oscilloscopes) that took some tens of minutes to fully “warm up”. I was very glad to see the back of such delays with the advent of transistors. But I cannot recall valve audio amplifiers that would not work satisfactorily within less than a minute of switching on.

No properly designed modern amplifier should require even two seconds to reach satisfactory operating conditions, never mind two days.

Leaving a power amplifier switched on when it is not being used is just wasting energy and is also a fire hazard.

My present amplifier has been switched on and off at least ten-thousand times during the past twenty-four years with no problems.


Alan
 

dazza74

Distinguished Member
In the nineteen-fifties and ‘sixties we had valve test equipment (such as oscilloscopes) that took some tens of minutes to fully “warm up”. I was very glad to see the back of such delays with the advent of transistors. But I cannot recall valve audio amplifiers that would not work satisfactorily within less than a minute of switching on.

No properly designed modern amplifier should require even two seconds to reach satisfactory operating conditions, never mind two days.

Leaving a power amplifier switched on when it is not being used is just wasting energy and is also a fire hazard.

My present amplifier has been switched on and off at least ten-thousand times during the past twenty-four years with no problems.


Alan

Fair to say you've had your money's worth out of that amp :thumbsup:

I've still got my original kenwood stereo amplifier hooked up to my CD player that must have over 10 years on the clock and still works no problems.
 

Badger0-0

Distinguished Member
In the nineteen-fifties and ‘sixties we had valve test equipment (such as oscilloscopes) that took some tens of minutes to fully “warm up”. I was very glad to see the back of such delays with the advent of transistors. But I cannot recall valve audio amplifiers that would not work satisfactorily within less than a minute of switching on.

No properly designed modern amplifier should require even two seconds to reach satisfactory operating conditions, never mind two days.

Leaving a power amplifier switched on when it is not being used is just wasting energy and is also a fire hazard.

My present amplifier has been switched on and off at least ten-thousand times during the past twenty-four years with no problems.


Alan

I seriously doubt that's correct, seeing as the top of my amp hits 40C :).
I'd guess the components themselves are a lot hotter than that.

Also, although I'm not sure I quite subscribe to this, I've seen it written a few times that people think an amp sound-wise, doesn't reach it's optimum for about a half hour.

Also, why do most electronic manuals recommend a warm up period?
Even Avia and DVE do the same.

But then, I'm picking flies :)

I totally agree with the waste side of the argument :smashin:

But I doubt anything made today would last 24 years :D
 

Badger0-0

Distinguished Member
Duh, I forgot.
I can't see the two days thing either :)
 

cooky560

Standard Member
My amplifier has been working fine since the 90s (Pioneer A-400) I just wondered if I am getting the most out of it, based on what I read.
 

Alan Mac

Well-known Member
I seriously doubt that's correct, seeing as the top of my amp hits 40C :).
I'd guess the components themselves are a lot hotter than that.

Also, although I'm not sure I quite subscribe to this, I've seen it written a few times that people think an amp sound-wise, doesn't reach it's optimum for about a half hour.


The fact that an audio amplifier may take several hours before it reaches a state of thermal equilibrium (ie. “its temperature stops increasing”) should not mean that the electrical performance is sub-optimal during this warm-up period.

If it is (sub-optimal), the amplifier is badly designed.

It is reasonable to expect an audio amplifier to reach its full performance within a few seconds of switching on.


Alan
 

Mark Botwright

Distinguished Member
I seriously doubt that's correct, seeing as the top of my amp hits 40C :).
I'd guess the components themselves are a lot hotter than that.

Are you saying that the components are supposed to be that hot in order for them to work properly?

TBH i can understand why some kit may need a minute to warm up but surely leaving something on 24/7 will not produce noticable differences.
 

Rob20

Well-known Member
I have heard/read it's preferable to leave an amp on. I tend to leave mine on standby although this could well be pointless. Still it's mainly because my universal remote can only put the amp in standby and I'm too lazy/forgetful to turn it off properly.
 

Badger0-0

Distinguished Member
The fact that an audio amplifier may take several hours before it reaches a state of thermal equilibrium (ie. “its temperature stops increasing”) should not mean that the electrical performance is sub-optimal during this warm-up period.

If it is (sub-optimal), the amplifier is badly designed.

It is reasonable to expect an audio amplifier to reach its full performance within a few seconds of switching on.


Alan

You said earlier "satisfactorily".
That is not the same as optimum.


It is reasonable to expect an audio amplifier to reach its full performance within a few seconds of switching on.

Debateable and as far as I know not proven either way :)

All I know is, I can't hear a difference between stone cold and having warmed up. But some apparently can.
So I don't discount it :)

As I said it's no big deal to me.
 

Badger0-0

Distinguished Member
Are you saying that the components are supposed to be that hot in order for them to work properly?

TBH i can understand why some kit may need a minute to warm up but surely leaving something on 24/7 will not produce noticable differences.

I'm saying they need to be at a stable temperature to be optimal.

Only my opinion, but things do change with temp :smashin:

The amount of time is debateable, but it isn't seconds, in my opinion.

I may of course be wrong, but feel I'm taking a sort of middle ground.
Seconds, no; Days, no too.
 

co55ie

Active Member
Thermal cycling is the main theory behind leaving an electronic item switched on. The components and circuit boards heat up and expand and cool down and contract, this can cause dry joints etc etc on the circuit boards causing the bit of kit to fail. These days things are generally made to higher tolerances so I cant see it being such a big issue as manufacturing techniques have moved on.

Having said that when do most items fail from a lightbulb to a television ? Most times in my experience its not when your using them its when you turn them on.
 
T

trevor g

Guest
hi, my nad c350a amp has been switched on from the day i bought it three
years ago, along with 542 cd player. contacted nad and they said leave it
on! regards trevor.
 

Andori

Well-known Member
Having said that when do most items fail from a lightbulb to a television ? Most times in my experience its not when your using them its when you turn them on.

AFAIK, it's the inrush/power surge that will typically kill most electronic devices, they are generally unlikely to just fall over and die in steady state operation.
 

Mrhappy37

Member
With a well set up quality hifi system you will hear a difference between kit that has been on for a long period rather than just switched on. Personally I can hear the sound getting better for a couple of days, this is fact not theory, although the warm up time could vary for different systems.

Also, it is normally the inrush current that will kill a piece of equipment as this is when it is usually most under stress.

Trevor G, have you ever tried turning the power off for a while then turning back on and listening to the difference?
 

Dave777

Active Member
Electrolytic capacitors don't last forever, leaving the amp on all the time will deteriorate them gradually. May still last for a long time time, maybe not. If I turn my amp on in the day I leave it on till evening (unless leaving house, when I always turn it off) then turn it off when retiring. My PC's are treated the same.

Dave
 

Mark Botwright

Distinguished Member
With a well set up quality hifi system you will hear a difference between kit that has been on for a long period rather than just switched on. Personally I can hear the sound getting better for a couple of days, this is fact not theory, although the warm up time could vary for different systems.

Can you prove this fact with hard evidence?
 

bsimmer3000

Active Member
well i always thought for digital equipment, when a electrical piece of equipment is cool it will run a lot better i.e cables and transistors have less resistance the lower the core tempreture. just like pc users getting stupidly high ghz from a cpu i suppose a amp could work in the same way. less resistance equals better sound quality. but like some people say it might also be like a car and takes a few mines for the engine to warm before it will produce any decent power. but then again an engine and a amp are not really the same lol
 

james.miller

Well-known Member
everything has an ideal operating tempreature. cooler does not always equal better:)
 

Mark Botwright

Distinguished Member
I suppose the problem we have here is that it is almost impossible to define "better". There may be a slight tonal difference due to differing temperatures but how do you prove that one sound is how it's supposed to be.
 

DaveC

Active Member
From an electronics POV there is no reason why leaving an amp on for a couple of days would make it sound any different to only being on for a few minutes. Modern amps use semiconductors....which will reach operating temperature quickly (probably less than a second for most).

I can believe that it may take a few minutes for an amp to reach it's optimum operating temperature, but this is not down to the semiconductors rather the heat sinks connected to them. Heat sinks will take some time to reach a stable temperature (measured in minutes not days)...the time taken will depend upon the mass and material used for the heatsinks. Small heatsinks will heat up in seconds.....large heatinks like the ones attached to the main amplifying transistors will take longer. The main amplifying transistors will affect the sound quality and will have been designed to operate optimally within a certain temperature range.

If it took days for the components/heatsinks to reach a steady temperature, this would imply that the heatsink was inappropriate for the job....the purpose of a heatsink is to dissipate the heat generated by the attached semiconductor...which it needs to do quickly or the semiconductor will overheat and probably fry!

As far as longevity of the amp goes there are a couple of things to consider:

Semiconductors suffer from something called metal migration (sometimes referred to as electro migration)...this is a slightly weird process where the metal that makes the interconnect tracks inside the device actually moves over time in the direction of the current in that track. Over time this thins the track and it will eventually blow like a fuse. This is why overclocking a CPU can shorten its life...running it faster and consequently hotter exacerbates the metal migration process . Modern semiconductors are very carefully designed to ensure that the metalisation is sufficient to last many years. I think consumer electronics is design to last 10 years continuous at 150C core temperature. However mistakes can happen. The more complicated the semiconductor the more likely it is that there will be an incorrectly sized track that has been missed in the design process....this will most likely affect complex analog/mixed signal chips like AtoD and DtoA converters as the silicon layout design is usually done by hand.

As co55ie said the heating and cooling effect of powering on and off an amp can impact its lifespan and to a lesser extent the transition currents (spikes) that occur on powerup...although this shouldn't be a problem in a well designed power supply.

So....to leave on or to switch off? If it's a good quality amp from a well known company....switching on and off will not do it any harm at all, you might eventually wear out the power supply switch, but the important stuff in the amp will last longer, you'll use less electricity, and your front room will be cooler in the summer.

If you genuinely believe that amp sounds better after a couple of days....you've probably also spent alot of your cash on solid gold speaker cables, plug-in devices that make your mains supply more sinusoidal (lol) and a really excessively expensive power supply cord too. (a belief in homeopathy is also probable)...it's all down to physics in the end.

Sorry this has turned into a bit of an essay/lecture (I actually deleted about half of this post coz it was getting a bit silly).
 

The latest video from AVForums

LG CX Best Picture Settings
Subscribe to our YouTube channel

Latest News

Samsung rumoured to be buying OLED TV panels from LG Display
  • By Andy Bassett
  • Published
Netflix signs with Sony for first streaming rights in U.S.
  • By Andy Bassett
  • Published
Audio Pro launches C10 MkII speaker
  • By Andy Bassett
  • Published
THX launches Onyx MQA supporting DAC/Amplifier
  • By Andy Bassett
  • Published
Cambridge Audio introduces Evo all-in-one audio system
  • By Andy Bassett
  • Published

Full fat HDMI teeshirts

Support AVForums with Patreon

Top Bottom