Not Eco Friendly

[Leonard Smalls]

My class AB Bryston hifi power amp uses 215W at idle - i.e. just switched on.
Full rated RMS power is 968W into 4 ohms, and the amp itself is rated at 2200W; this means that peak power is 1382W/ch into 4 ohms, so it's a total peak power of 2765W, which is considerably more than the rated power...
Which means that the relationship between current draw and sound output isn't quite as simple as a few rating figures might have you believe...
And in addition to this, sound output is dependent on the efficiency of the speakers, then different frequencies need different amounts of power to produce, then there's etc etc!

[BassTractor]

[quote name='Shonks' timestamp='1444382250' post='2882689']
Switching it on, it read .083 kw
[...]
Switching on the Markbass (at low volume) and it went up to .116 kw. turning the volume up .119 kw.

I think my reading is per hour.
[/quote]

It's not per hour though. It's the Wattage (a level) at that very moment.
If you use 1,000 W for 1 hour, then you'll have used 1 kWh.

The meter tells you that the MarkBass uses 116 - 83 W, which is 33 W.
When you then turn up the volume, this goes up to 36 W. This is as predicted. The 25 W amp would use slightly less electricity for the same volume of sound.

[leftybassman392]

Note to OP: if any of the above is making your head spin, don't worry about it - you're not about to drain the national grid - not even if you turn it up and play loud!

In simple terms the number on the back indicates the possible power draw at maximum output. At the sort of levels your using them at I doubt either one would draw enough power to light an old-fashioned light bulb... maybe the Markbass - just.