Amp — Leave on or turn off

I always turned my Benchmark AHB2 amp off after use every night. After all, why is there an on off switch on the front panel if not to do that? Last night I accidentally left it on. This morning, when I played my first record, I couldn’t believe my ears. The same record I played last night sounded infinitely better. I tried a second record and that, too, was much better.
I know there’s a debate on the question of leaving an amp on all the time.
I now know where I stand!


Have you listened in the morning before when the amp was off all night and had a different result?   Personally, after being in a dead quiet room for 8 hours, my ears are much more sensitive in the morning then the night before.  Even when I listen at night, or during the day, I try to have some quiet time before I listen.  Relaxes me so I can better enjoy the music, but also gives my ears a rest.  

I left my McCormack amp on 24/7 (unless we were leaving for a week or more) and only had to replace a fuse over 20 years.  McCormack recommends leaving the amp on I think partly because many electronic parts don’t like constantly cycling between cold and warm, but I know some other manufacturers recommend turning it off so may be product specific (obviously you don’t wanna leave a Class A or tube amp on).  Anyway, I’m with you on just leaving it on.

And there is often less electrical activity in the neighborhood mornings.

I often forget to turn an amp off overnight for no net gain in SQ.

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I agree with both 12many and fuzztone ,  I turn my McCormack amp on about an hour before listening , enough time to warm up .

My AT3002 amp has a standby mode feature. I think it keeps the amps circuitry charged up some.

I usually turn it on about an hour before using.

It’s not a debate. It’s very much amplifier specific.

I have ICEpower amps and they absoultely need at least 72 hours to sound musical.

My Luxman warms up well in half an hour.

I have no real explanation for why some amps warm up faster than others. I do not believe this has anything to do with the amplifier class (A, A/B or D) either. I do think it probably has something to do with the capacitor types, and maybe how much power they draw at idle. Perhaps the Class D amps, being low power, take a lot longer to warm up because they literally don’t warm up?

I’ve also heard say certain megabuck amps simply don’t sound good until after 48 hours at least.

I think it’s very much specific to the amp.

I notice that my amp sounds better after I eat a croissant.


Hard to say. ;-)

I have the PS Audio S300 stereo amp and the M1200 monoblocks and was wondering the same thing. Just left a message at PS Audio. Curious to hear what they say.

Well, I called Benchmark and they say there’s no advantage in leaving it on all the time unless you have an investment in the power company.

Guess it’s my imagination or my mood. 
I’m still leaving it on though just in case.  
The technician says it makes no difference as it draws very little current.

@rvpiano   Would you leave your car running when you're not using it?  Wouldn't really hurt it but would be illogical.  The same applies to your amp IMHO.  Everything has a natural lifespan and heat is no friend to electronics.  Unless someone can show me how an amp benefits by being left on, I follow the manufacturer's advice and turn it off.  But not everyone agrees.  Cheers.

Tube stuff gets shut down when I'm not near the room or ready to go back; some solid state stuff needs to be plugged in for a long while before it comes on song. 

I used to have a Lamm L2- two chassis line stage with a solid state audio path and tube rectification. Vlad said to keep it on all the time, which I mostly did (in NY) except during fierce electrical storms. It took days to come back on song from a cold start.

There's a piece by Sear of Sear Sound about shutting off recherché gear. You should be able to find it on the open web. 

@soix "..but I know some other manufacturers recommend turning it off so may be product specific (obviously you don’t wanna leave a Class A or tube amp on). Anyway, I’m with you on just leaving it on."


My primary all-tube system with tube preamplifier and mono tube amps have easily accessible on/off power switches. Warms for 45m prior to use, does ok.

Now the secondary system I’m working on now, solid state Class A amp has a power switch on front, and yet the matching Class A preamp has no power switch at all. Plug in the preamp, and it’s left powered on all of the time, as designed.

I can honestly say both systems do sound better, or at their best, when all of the components are good and warm, big iron transformers extra warm and saturated at 4+ hours. What was odd and memorable was rechecking after being left on for 24hrs, could usually hear something a little extra special or more engaging each time. Same occurred with many of my former Class A/AB dual mono solid state amps.  Reaching that optimum sustained operating temperature perhaps. I try not to leave any of them on though for more than 4 days max, if I know I’m not gonna use it for a week or more fwtw.



This what others have already said, component dependent.  Our tubes amps change in about 20-30 minutes and can max out in 2 hours or less.

Happy Listening.

I think what the manufacturer recommends is irrelevant.  What matters  is your own ears, and your willingness to pay the electric bills. :D

If you can't hear a difference, leave your gear off.  If you can, leave it on.  It's that simple.  No measurement is going to tell you any better.

RV, I have repeated your experiment a number of times with the same results. On longer always sounds better, but with diminishing returns, for about a week.

Its’s true of my DIY phono/pre - it’s on all the time. It’s true of my DIY Class A amps (they idle continuously at half power). It’s true of my Bryston SST in the HT (although B recommends turning it off). But since HT doesn’t matter nearly so much, I do turn the B off, and then back on an hour before - but an hour isn’t really enough.

My cartridges take 10-40 minutes too.

As for the car analogy, I ALWAYS used to warm up my engine carefully, and my tires too, before taking a fast lap.


I had a Krell FPB 600 amp that I always left in the standby mode until I powered it up to listen. Was doing that for years and years. Then I have now the ARC Ref 750s. And I always let them warm up about 1 hour before listening. Happy listening. 

Class D / on 24/7

Class A / off

RVPiano - are you aware the Benchmark can be set for auto shutdown 

after 45 minutes of sensing no audio signal? Also the Benchmark handbook 

states that due to the SMPS power supply the amp is at its full potential the moment it is turned on. 

Class D / on 24/7

Class A / off

RVPiano - are you aware the Benchmark can be set for auto shutdown 

after 45 minutes of sensing no audio signal? Also the Benchmark handbook 

states that due to the SMPS power supply the amp is at its full potential the moment it is turned on. 

Both my Hegel H390 and my PS Audio gear all stay in standby mode until I wake them up. Both take less than an hour to sound great.

@kckrs In my experience, Class A/AB also on 24/7 unless traveling. We really should follow the mfr recommendations. And if you bought used, the manual is available online.

Hello Hickamore

The manual on my FW F3 from Nelson Pass 

states - "I do not personally see a reason to run the amplifier

all the time, but you can do that if you want to ".

"Also, at 200 watts it makes economic sense to shut

the amplifier off if you aren't planning on using

it for the rest of the day".

I'm sure this recommendation follows on my F5

and XA25. All of course running in full Class A.

@bigtwin -- Amen.


Other members that have chimed in know a lot more than I do, but the only thing I would add is this...If you do plan on leaving your electrical components on 24/7, make sure your Homeowners Insurance Policy is paid each month and hope that a Fire Department station is near your house.  As some of us unfortunatley know, sh*t happens.

I used to have an Adcom GFA-555 that I left on all the time.

When I got back into audio gear during COVID and purchased some Aragon gear, it very clearly stated in the owners manual to turn the amps off when not in use.

After being between those two extremes, I'd probably think letting the equipment warm up a bit isn't bad, but I see no need to leave SS equipment on all the time nowadays.

To each their own.

It is, as many stated, amp specific. I will add that it is also user specific. In my case the weekends are my music time, so my system is off all week. When I get home Friday night, I turn everything on and leave it until my weekend is over. My Macintosh gear always sounds better by Sunday. Could be the bourbon helps some. I am going to do more studies. Wish me luck.

Much has todo is how much power it sucks up ,A pure class A amp runs full bore so no to Thst one ,a class D amp if you wanted why not  a amp takes about 30 minutes to get to temp  and if newer the capacitors and transformers could take 

months to fully settle in. Depending how much you play it.

My Pass XA 60.8 power amps take an hour to warm up and the sound quality improves slghtly over the next hour. There are no further gains to be made from leaving the amplifiers on when not being used from listening - except for warming up the room, but that's a very expensive form of space heating and not recommended.

if it's a solid state amp it needs to be on all the time, I have a sim audio w8 and if I turn it off after 24 hours it needs to warm up for 3 days again before it sounds totally open again.

This thread is going EXACTLY the same way as the last one, and the one before that........    You say Tomato and I say Tomato.  You want to leave our equipment on, then leave it on.  You want to turn it off, then turn it off.  I doubt the argument has ever changed an opinion.  Time to move on to a new topic.  How about "do power cords make any difference?"  🤣 🤣 😭

@rvpiano you can leave all your benchmark components on. Extreme heat is the enemy of electronics. The SMPS doesn’t draw much from the wall and there’s no energy to convert to heat. So you’re safe to leave it on if it sounds best to you that way. No harm.
With my Pass X260.8 mono amps that are Class A biased for the first 35 watts, I put them into standby when I’m done listening. They take couple of hours to come to temperature and sound their best which is ok to me. The space heating is an added benefit in the winter 😂

If you have a tube preamp... turn it off because logic would tell you that you are putting time on the tubes.... Haven't seen any studies but it makes sense (I'm going to get 10 posts telling me I'm wrong). I've noticed that temperature and humidity makes the most difference in how my speakers sound even though those are only slight changes in my listening space.

There is what’s right practical and then there is what’s right to keep the the itsie bitsie brain worms from eating away at your pleasure center. My advice based on you OP is leave it on. Excessive heat is what kills electronics soooo. add cooling fans as needed to the hot parts as needed. Usb powered lap top coolers work great! Get a "Watt Power Meter Plug Home Electrical Usage Monitor" to see how much juice your amp uses over night (Less that $15 on amazon). This will kill that brain worm. Benefit will be you now will have an on/off switch that will last forever (a whole other topic of conjecture) .

Enjoy the music and as Van the Man says - "turn it up, little bit higher radio
Turn it up, that’s enough, so you know it’s got soul
Radio, radio turn it up, hmm La, la, la, la, la, la, la ...........

My Pass Labs XA-60.8 mono blocks are class A and leaving them on would bankrupt me :). But they have a standby mode. They warm up fully after about 30 minutes. Like others have stated, it’s amp specific. If you change to another amp, consider one with a standby mode.

I have been leaving my refurbished Audible Illusions preamp on to eliminate constant cycling on and off supposedly to extend tube life. The pre stays barely warm to the touch. Sounds great. Solid state amp on and off per use. 

Considering that the most common mode of failure in an electronic component is thermal fatigue from power cycles, I leave my system on most of the time. I turn it off for thunderstorms and if I will be away from home for an extended period of more than a couple of days. 

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Responsible Conservation: Totally irresponsible to leave anything on!

I sometimes wonder how much collective electricity is consumed world wide for standby/instant on devices.

The lights aglow in my office at night are like an un-named constellation

I don’t have solar panels. Does this mean I can resume playing Peel Me a Grape that I had on repeat for close to 30 years in my high power consuming system? Cause I just paused it for few minutes to check if I kept that coal plant alive all this time….no bueno there…the last of the mohicans in NJ it was demolished few years ago. 

There are close to 220 operational coal power plants in the US. China has over 3,000.
Our contribution to pollution by leaving our amplifiers on can’t even be measured. I’m not saying we don’t need to be conscious about it, but the environmentalists on this thread…you guys are barking up a wrong tree.
Alright enough politics…hate this in the audio forum. There are other places where this can be debated.

For my Portal Panache Integrated (designed by Nelson Pass), they recommended that for best sonics it be left on 24/7 (there was no standby switch)...for my high power Pass Class A mono blocks, Pass says there is no short or long term harm in leaving them on 24/7, simply my decision based on listening habits, sonics, electric usage...sure seems manufacturers of seemingly similar products have various recommendations...

A class D amp takes 24 to 48 hours to properly charge the caps and settle in since it is 95% efficient. You don’t want to EVER TURN ONE OFF SO HELP YOU GOD unless you are plugging in things into it

Electronics degrade by cycling on/off , true but to what extent ?  leaving on 24/7/365 equals 8,760 hours per year , since most power/filter capacitors are rated for 10,000 hours which would you think causes the most degrading ?  How often do you plan on replacing the electrolytic caps ? how long do you plan keeping your amp ? 

Newer amps have standby modes , older ones are on and off only .  The new Krell 800 watt mono block uses 1 watt in standby and 260 watts on with no music so leaving it in standby is like turning it off , you wouldn't leave it on using 260 watts would you .  My 250 watt amp uses 84 watts at idle/on , there isn't a standby mode so leaving it on is not very practical .

If leaving your amp sounds better to you then do so but think about the true cost depending on the amp you own .


I use my HT system Friday/Saturday/Sunday. Mon-Thurs the wife and I are in our living room. I used to leave everything on. But then figured if my system was going to be completely unused for 4 days, wouldn't it be better to power everything down? So only recently have I started doing that. And I mean I power everything down, DAC's, Processor, Amp, Streamer, and all 4 of my subs. I actually flip switches powering everything off fully.

Then on Thursday night before bed I power everything up. I don't play the system. Then fist thing Friday AM before work I run the streamer at low volume and let it play all day so it's nice and warmed up by the time I get home.


Then everything stays on until Sunday night when we go to bed all switches off.


I'm sticking with this routine😁

That amp uses 20 watts on idle. That's less than a low wattage lamp bulb. If it sounds better leave it on!

AC Input

  • Auto-ranging AC Input
  • 100 to 120 VAC +/- 10%, 8 Amps, 50 - 60 Hz
  • 220 to 240 VAC +/- 10%, 8 Amps, 50 - 60 Hz
  • Idle Power Consumption = 20 W
  • Standby Power Consumption < 0.5 W

My pass Labs INT-60 manual tells me that it was designed to stay powered on so I changed my practice of putting in stand by and I just leave it in now