System power off/on

Since electricity prices are due to rise significantly soon I was wondering what the cost is to keep the system on at all times as recommended?

My system is 72/HiCap/250 a mix of CB and Olive. I have always kept it on except for holidays. In addition to the cost question I was also wondered if I was to leave the system off is there an ideal warm up time say 1 or 2 hours?

I’d highly recommend to fork out $15 for a wattmeter. Program in your price per KwH (I’d go for the mid point price between your on and off peak rate) and measure it yourself. You’ll have an exact answer for the bits you have.

Brilliant devices reveal a lot about what costs the real money to run in the house and what things you think are costing money are just nonsense myth. Spoiler alert, phone chargers etc, consume nothing when not charging your phone so unplugging from the mains saves you nothing.

Take a look here…

“ideal warmup time”

In my experience, NAIM boxes take three days to warm up, but are “listenable” on the first day, “mid-range vocal honky” on the second and blissful after the third.

As ever. you pays your money and takes your choice.

Leaving it all on is an essential, afaik.

Take down the central heating a couple of notches and wear warm clothes indoors…


If have a meter that will measure the power being drawn from the supply but it won’t do the cost calculation for you, here’s how to do it:

  • Measure your system’s total power consumption in Watts (or preferably Volt-Amps, if your meter can distinguish between the two) with everything idle, and call this value P
  • Divide P by 1000 to convert it into kilowatts, call this value K
  • Multiply K by 8766 (the number of hours in a year) to find the number of kWh used keeping your system on but not playing music for a year
  • Multiply this by the price you’re paying for 1 kWh (using an average value if necessary, as @feeling_zen suggests)

For example, if your system’s idle power consumption were 30 Watts and you’re paying 20p per kWh, that would be £52.60 per year, or just over 14p per day.


I think I read that power amps can be switched off as they warm up in a few hours but, practicaly, other boxes need to be left switched on.

Here are my costings based on the coming April capped Tariff, and using a Watt meter


Do you have any electric heating or cooling? I did a recent exercise the same as you and when I got to the AC (which is the only heating we have in winter here too) and dryer the numbers were astronomical. The hifi and everything else was just a rounding error in comparison over the course of a year.

My hierarchy of consumption was definitely

  • 80% heating/cooling
  • 15% computers and monitors (both my wife and I work from home)
  • 5% everything else

But I managed to tweak the dryer and AC settings to shave off over $100/month from the energy bill without any noticeable reduction in heat/cooling output. So the wattmeter paid for itself several times over after just one month.

No electrical heating, hence why I can concentrate on the low items using power. The biggest thing I found was the old inside freezer which I replaced when I realised how bad it was. It was picked up via freecycle by a lady who’s current freezer would freeze up too much, so overall not completely environmentally unfriendly. As you can see, that move alone saves £90 a year.

My specific aim initially was to try and understand why the house was using >300Watts all night when we are asleep. Currently it now moves between 170 and 260, so happy with that, and feel better about leaving the HiFi on.

BTW, being in England means very few here have cooling facilities other than opening the windows, and cheap little noisy fans to spread the heat around

Left my system always on. XPSDR/CDX2,555PS/NDS,NAP300 and NAC252/SCDR. Power consumption some 80W,which amounts to some 700 KWh annualy. 20% of my electric consumption bill.
Anyway,as a test,powered everything off and only powered it on when I want to listen music. No audible difference,everything sounded just as sweet as when I left everything powered on. So now everything gets powered off after listening. Cut off 20% of my power bill. And no disadvantage. No brainer imho. But as always, YMMV.

Mark my words. Naim will be working on class D as we speak.

I’d love to be able to turn mine off and not hear a difference. The sound is always a bit thin and anaemic when first turned on, so it stays on. I have my NDX2 set to go into standby, which of course you can’t do if using an external supply. As @Martinzero says, Naim must surely be working on ways to cut consumption. And if they are not, they should be. It’s not just the cost of course, but the impact on the planet.

They did venture down this route a while back with the Tripath amp modules in the n-Vi.

That is alarming. Represents my monthly electricity bill just running your hifi for a year!

Presumably that includes listening time. What sort of duty cycle do you think your listening is? For me its a couple of hours in the evening about 8% listening time…

I am of course assuming it draws more power when you are playing music😁

In my case, listening increased from an idle 56Watts to 75-95 Watts, so yes that is a higher cost, but that is only 1-3pence for a two hour session - well worth it in my opinion

Why not? I have my NDX2 go to standby with an external supply, it surely is possible, and if nothing draws power, the supply by itself shouldn’t, either (I guess).

(My reason for the standby is to make the screen turn off and I have server mode on to keep warmed up)

True standby on the NDX2 switches to the internal SMPS. Something you can’t do when using an external PS.

Sure, but you can still send it to standby and it will use less

A bit less, but you still have the whole external PS powered up.

Just leave it on. It will go off song otherwise