It’s not so much the watts it draws when running, each transformer will pull many times more than the total in the first few seconds of startup.
Have a look at your intended PSU to see if start up inrush current is covered.
Ah ok. If you can get a dedicated line in then that’s where I’d start rather than the power conditioning / regenerator route. If you’ve got flickering lights when loads are changing in the house then it may also be worth getting an Electrician in first to check all is well with your supply and breaker panel.
From your description, I’m assuming you’re not in the UK ?
To answer your question, there are a couple of places to look. Firstly there should be a label on the back showing the Voltage and Current or Wattage setting.
Also check the manual, e.g. found this on Naims website, suggesting 10VA (which means 10Watts). Of course this doesnt account for the initial switch on boost, but typically you should only turn on one device at a time, with a few seconds gap in between
You can buy a power monitoring plug which you plug into the wall socket and the appliance plugs into the monitor, it gives a read out in volts, watts, amps and kWhrs. Response is on the slow side but will give a good idea on continuous music passages.
The answer during steady state use will be ‘not a lot’ and very unlikely to be enough to cause a problem, may be 100 Watts?
Depending on where you are located, the power grid may also be suffering. I have used quite regularly a voltage measuring device at the many locations I have been in. Worst was actually in Saskatchewan where over the course of a day the line voltage would drop to as low as 108V and go as high as 130V. Many people, especially rural consumers would use a large whole house Toroidal Transformer to regulate the current as much as possible.
You mention that everything is better during the evening. This could be due to decreased industrial loading of your local power grid during the evening hours (factories and heavy industry not drawing as much power).
As some have suggested, a dedicated circuit from the breaker box to your system will solve some of the issues. If you continue to notice a difference between daytime and evening, then the local power grid may be in need of upgrading (or an additional transformer on your local grid ).
I run a Naim active system (3xNAP300) that is on all the time. The power draw is less than that of my 1500W computer power supply. The power draw of your Naim system is not the issue.
If you can, monitor the voltage swings over the course of the day (and night) as I bet your computers and AC unit are also affected by your local power grid loading.
Do you currently have 60A, 100A or 200A service from the power pole to your house?
@akessel I’m in the US. I do both . I have Two dedicated 20amp circuits . My definition is: Single 20amp breaker, 10awg romex , 1 high quality outlet, such as Oyaide or Furutech. That’s what I have x2 .
The PS Audio units are I think a bit overpriced. Keep in mind that none of the them include a good power cord. The Power Plant 12 is $5k and the Power Plant 15 is $7500. AudioQuest units that many folks on this forum like are also a great choice. The Audioquest Niagara 3000 is $3000 and the Niagara 5000 is $5000.
Then there is Shunyata Research. I’ve used Shunyata for years. I like that unlike the PSA units they are more passive, and have a lifetime warranty. I use the Shunyata Denali 6000S v.2 , with a Shunyata Alpha XE PC to the wall.
Lots of good reviews on all three brands. I’d recommend you start with the dedicated lines it’s relatively inexpensive and the first place to start.
Standard tower case power supplies are now pretty much 750W with some higher performance units requiring 1000W supplies or greater. The tower unit generates almost as much heat in a small room as a large plasma TV or an old tube stereo amplifier! Great for heating rooms at the extremities of the house in the winter The number of computers on in the house during this Covid period as we
work from home here has definitely increased the monthly power bill by a noticeable amount.