Can you leave class D amps on and not ever turn them off?


Can you leave class D amps on and not ever turn them off?

rvpiano
If you want. SOme audiophiles leave class A/B amps on all the time, even though they are much more power hungry when idling.

I have a pair of ICEPower 250 amps which idle around 14W totall.

It helps to have a reliable surge protector though in case there is lightning while you are out.

Best,


Erik
Sure,why not? My mono blocks were designed without any power on/off switches incorporated. All is good.
Always turn off your amp does not matter A,AB or D then turn on 1 hour before listening this should be plenty.
You SHOULD keep class D amp on 24/7.

A reliable surge protector might not help if lightning strikes, so if that's the case of such vulnerability, than turn on and worm up for 20min and than enjoy the tunes.

Class D amps as no other amps can be on stand-by forever. It will make their life longer than if they're completely turned off for months.
Do what maker recommends.   Bel canto recommends my amps be left on so I do normally except if away for more than a day.   Class D should draw minimal power when idling and does not generate much if any heat due to efficiency so that makes it more practical in general.
My Triton's have a class D amp (bass amp) and there is no power switch on the speaker. The manufacturer (Golden Ear) merely states that when an audio signal is present the amp is "on" and when no audio signal is present for a period of time (20 minutes or there about) the amp goes into "stand-by". However, even in standby mode they do draw power (albeit very little) and for that reason and other piece of mind reasons when I'm not listening I power them down via a switched power conditioner I have them connected to. I only turn them off when they have gone into standby, not while the amp is still actively on (as evidenced by an LED). 
Thanks for all the responses.  
They are a little mixed.
The concensus seems to be to leave them on.
I've in the past always turned them on and off, and have had trouble with one balking at startup.

FWIW, the BEl Canto ref1000m amps draw a lot of current when powered up.    If I power both up at exactly the same time, my circuit breaker will break.   Once on though there is never an issue.

So a major power draw event like that is likely best kept to a minimum and is an indicator to me that its best to leave them on if possible.
My Class D Lyngdorf stays on all the time and sounds much better this way. Big difference. I always leave it on unless I am out of town for a week. At least with my amp there is a night and day difference. One hour did not do it. I have had the same experience with other SS amps. 



Regarding sound quality when leaving on versus turning off,   I suspect leaving it on at it should be only helps but have not been dissapointed either to-date after firing it up cold.
Can you leave class D amps on and not ever turn them off?

Yes.
I don’t trust SMP power supplies, they are finicky to component (caps etc) aging

Most Class D’s use smp (switch mode) power supplies, they do go up in smoke a bit more frequently than linear ones, and can be a fire hazzard if not at home.

Cheers George
I always leave it on unless I am out of town for a week. At least with my amp there is a night and day difference. One hour did not do it. I have had the same experience with other SS amps.
+ 1
Mine is a dinky and has been left on 24/7 for the most part, only shut down if out of town for long periods.  No noticeable 'start-up' issues, but it's as simple as a pet rock...*G*

I have had the following class D amps in my system over the years: Bel Canto REF500 and REF1000 Mk.2. Rowland M312 and M925. In all cases, I have left them on 24/7 while monitoring the local wheather like a hawk. Whenever thunderstorms are in the forecast for the day, I always turn off the entire system and unplug each component from the AC outlets.


BTW, with all amps that I used in my system, class D and A/B alike, I have experience that the audible behavior is maximized if left on for about 24 hours while generating some kind of low volume sound... I usually connect an old FM tuner set to interstation hash.


Class A/B amps have included Aragon 4004, Rowland M7, Rowland M625, Rowland M725. All benefited from being at full power 24/7... Invariably took 24 hours for any amp to run at its sweetest. It was possible to run M625 and 725 24/7.... Tried that on the old M7: costed me $150 of AC over a two weeks stretch *Grins!*

 


BTW, I have never experienced an SMPS giving up on me.... All have been rock solid.

     

BTW, I have never experienced an SMPS giving up on me.... All have been rock solid.
But if/when they go, it’s with far more fireworks that linear ones, and they’re not as tolerant to being out of spec as linear ones either. When/if just the caps leak in linear ones they just smell and sound crap, but smp ones can go up big time if the caps go out of spec.
I repaired too many to trust them being left on and home alone, and it’s usually the whole smp board that has to be replaced as the boards/tracks get fried/burnt beyond being fixable.

Cheers George
George can you give us a couple of examples of the ones that go up in smoke?
I think that leaving any component on permanently can cause it to lose its best performance. Even Paul Mcgowen said if you unplug all your components from the wall and then plug them right back in, it can actually improve the system's performance.
Depends on the design of the component. Some sound far better and last longer staying on. 

Hi Ph.D.... YOu are absolutely correct.... I have observed the same thing, and should have mentioned it.


Fact is that with all my amps, class D and class A/b alike, I turn them off once a week for a couple hours for the very reason..... After a week or more days of running continuously, the sound just sags a little bit.... Turning them off for one or two hours and powering them up again freshens them up nicely.


Regards, G.


Ok, I will turn my amp off for a tad and then let it warm up for a couple of hours and see what we get. I assume it still sounds best always on, but just turn it off for a tad after a few days. Strange, but I am open minded.

I know my Class D amp sounds far better after being on 24 hours. 


Guidocorona, it couldn't hurt anything to try on occasions as long as you power everything down first. You could actually leave the system unplugged for a few minutes then plug back in. This is a tweak that won't cost you anything.
George can you give us a couple of examples of the ones that go up in smoke?
Ones I remember
Panasonic PVR's, dvd/cd players, Samsung, Panasonic TV's,  2 x Velodyne CHT15 subs, 1 x Alesis 620, 1 x Nuforce 8 monoblock, 1x Halcro DM68 that had to be shipped back to manufacture. 1x Behringer B2031A, 2 x Behringer active xovers. 
These are ones that were left on or in standby.

Many others were blown and popped their fuse but didn't fry up. 
Countless smp battery chargers, some of them liked to fry with much crackle and big smoke.

Cheers George
I hope when their switching power supplies blow they won't destroy the speakers, but I suppose that is why they are protected by a fuse.
Grannyring, give it a try. Afterwards of course you will still have to wait for it to reach its optimum operating temperature for best sound but it will provide better overall sonics for a while. Let us know later if this made a difference.
George,

You mention NuForce 8 monoblocks as having gone up in smoke.
Would you suspect the Nuforce 9's as having  the same problem?

rvpiano OP
George,
You mention NuForce 8 monoblocks as having gone up in smoke.
Would you suspect the Nuforce 9's as having  the same problem?
Many use the same generic SMP boards from the same manufacturer just different rail volts, so it wouldn't surprise me if they were similar.
See this post of a Nuforce 9se v3 I posted in Stereophile and what it did to a reviewers pair of Wilson Watt Puppy 8's, this wasn't a powersupply issue just the nasty noises the 9se made.
http://www.stereophile.com/comment/561214#comment-561214

Cheers George


Thank you for your reply, George.
I own the original Nuforce 9's and have kept switching them on and off for years.
i guess I'll continue to do so, even though, for a brief period, I left them on and didn't have the annoyance of waiting for them to warm up.

Oh well.....
**Usually** keeping filter caps charged is a good thing for their lifespan. If however that means that the caps also are running warm then its not going to help, especially if some of that warmth comes from ripple current (which tends to be higher at higher frequencies as seen in SMPSs). Careful circuit design can avoid these problems.

As one who has spent a lot of time studying the idea of going off grid and using solar power and the like, one thing that comes up in sorting out how much power you're going to need is how long something is on, and not so much how much power it draws. Class D amps are typically around 85% efficient so a 500 watt amp is going to draw some power even if its just sitting there at idle. Since there is never dead silence even when the preamp is off, that means the output section is engaged even if its not making a lot of power reproducing background noise.

I get that some solid state circuits sound better after they are on for about a day or so. IMO this really says that maybe they aren't all that green compared to tubes if you tend to leave them on all the time so they will sound right.


Interesting thread. I'm using the trigger cables on my Wired 4 Sound mAMPs to power them on/off before/after each listening session. May try leaving them on for 24-hours to see how things go, but that sound pretty great with little to no warm-up time.
I'm running a Rogue Audio Pharaoh integrated. It's a hybrid- tube preamplifier and Class D power amplification. It also has two power switches. The front switch controls the preamplifier. The rear switch (meant to be left on at all times unless changing tubes or configuring the phono section) controls the Class D boards.
Transistors live longer when they're always ON.
They have life of up to 60k hours when ON and much shorter than OFF.
Electrolytic caps also benefit from being always ON except if under high temperatures. Leaving on even clas A/B amp isn't a problem if one does not dissipate excessive heat. The only now consideration is power line and if there's ever been an issue with lightning strikes. Than you will have to power down when leave home or at least when disaster is expected. There will be no surge protection of components if hit by lightning.
Class A solid state amps and tube amps always should be turned off when not attended.