I’m done arguing with you. You are either trolling or stubbornly confused.

+6dB when referring to amps and power/voltage as we are here and have been, is a voltage factor of 2x, which is a power factor of 4x. Hard fact. Period. Written in stone. +10dB (when talking about power factors of amps) is a factor of 10x power. Again, hard fact. Period.

Arguing points on something we aren’t taking about which is SPL in the air you are bringing up, aside from what the peak output level will be from a given power level serves nothing except to prop up your broken talking points and bad math.

You typed in 0.0001 mW rather than 0.001 mW

0.0001mW or 0.1 uW is at a power factor of ten less than a microwatt, again, a microwatt of power into this load makes for 70dB SPL output in this example. 100nanowatts is 60dB.

So, if people want to believe you, they are free to. But you are mistaken about we have been discussing, well, trying to. While I’m sitting here listening to a mastering converter with amp at no more than 4 uW and down to about 0.25uW or 250 nanowatts on this song that is averaging about -12dBFS with HD650. All known variables.

You know how I know this? A Stepped attenuator with 1dB steps, a known power output and also professional dBFS meters with peak values and average values. Along with the actual math needed to figure all this out. Even ~approx calculation is possible for a one dB step with an easy to remember power factor.

So, when I say to people, yes, an Apple dongle can drive most headphones pretty well… I mean it. I use one too. With many headphones. But it doesn’t mean it sounds exactly the same as a mastering oriented pro voltage level DAC/amp, especially when listening rather low.

4uW for 74dB peaks isn’t that outlandish is it? It’s like 33dB ambient right now.

Have a good one man.