Am I getting full speaker amp power to my headphones?

I found out that my speaker amp’s headphone out (Denon PMA 1500 RII) on 9 o’clock is as loud as my Topping A30 Pro on 12 o’clock (high gain, 5,5 Watts@32 Ohms) ,
so I’m wondering if I’m getting the full 70 Watts@8 Ohm ≙ 17,5 Watts@32 ohm.

Here is a picture of the headphone section:

What are your headphones?

lol no, they probably be smoking with that power.
Amps mentioned output is: Equalizer amplifier output: 150mV ? ohm

Beyerdynamic Dt 1990

I didn’t even turn the volume knob to noon because they already might explode there. So 17,5 W is not unlikely

Id say it is unlikely.
Since that power is not mentioned on the Headphone output of the amps specs.
You just cant make “more power” from something to something that’s not there.

There aren’t any amp specs.
Look at the circuitry. There is no op amp amplification and no resistor. It looks like it’s just tapping the output transformers like the Emotiva basx does when you remove the resistors.
And the output voltage is also suggesting that it’s just a speaker amp tap

So how did you know about the 70 Watts@8 Ohm on Denon?
Probably the same way i found the Headphone output: 150mV.
From the specs but i’ll stop now. No point going forward since i trust what is typed “with black on white”. Measure it to overcome the mentioned specs.

Where did you find the specs? I can hardly believe it’s only 150 mW since it easily outpowers my topping

That extrapolation assumes the amplifier is not voltage limited, which it very likely is.
Without measuring voltage going into the amplifier section and voltage drop across the headphone, no way to estimate power.