I am not recommending this, but you could turn the volume up carefully until it just begins
to clip (distort). At that point, see if the meter reads full power. That would be about the
simplest way to check the power meter accuracy.
And again, I don't recommend as I don't know the "health" of the components.
And anyway, the meter actually responds to signal voltage and will only be accurate for a
specific load. You may find the load impedance for accurate readings specified somewhere.
Volume perception is logarithmic. A 2x increase in volume requires a 10x increase in power.
Since most stereo speakers are 8 ohm, the meters might very well be calibrated for 8 ohm loads.
If that's the case the actual power for an 11 watt reading would be 22 watts.
(I assume you have 4 ohm per channel, two 8 ohm speakers each side)
That 22 watts is more than 1/2 full perceived volume. In other words, you would not be able
to double that 22 watt peak in perceived volume; that would take 220 watts.
So those low wattage levels can be a lot louder than you might expect. But it does sound like it's
reading lower than actual. About 1/2 actual, if my guesses are correct.
Last edited by megafiddle : 12-21-2012 at 08:30 PM.