How to understand amp outupt power?

I need help to understanding how amp output power works?
F.e. I was comparing my aune S6 pro (amp specs) with massdrop x Alex Cavalli Liquid carbon.
How compare the amount of power. How to calculate it.
In massdrop amp It have:
-Maximum power: Balanced 2.8W RMS into 50 ohms, single-ended 0.7W RMS into 50 ohms
Aune S6 pro:
Xrl 405mW 300ohm
Single ended 120 mW 300 ohm.
How to calculate it to directly compare. Can someone please tell me. Which one is more powerful and by how much?
How to compare 50 ohm to 300 ohm un terms of mW. If I have higher impidence I get less watts or do get need more watts? If someone could help I would be greateful.

Does this help? http://www.apexhifi.com/specs.html (spreadsheet calculator near bottom).

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ohms is resistance. the higher the resistance, the more energy you need to overcome the resistance, reducing the amount that reaches the headphone in this use. amps deliver X amount of power at a designed base resistance. then at X resistance you get XX% of maximum power based off of resistance. how the amp is designed to deal with the wide degree of variable resistances in headphones, along with quality of parts, can lead to variable amounts of power at different resistance points from amps with the same base power.

either way both those amps are right around the same power and will drive the majority of headphones. that is if you use the balanced outputs. the single ended are weak on both units.

i would suggest emailing aune and asking if they can give you the 50 ohms rating.

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Thanks a lot.

Amps power ratings aired based in the voltage and the current they deliver. They will have a maximum of both. And it will be limited by those maximums depending on the load.

For what you care about in terms of listening to headphones voltage is what makes things loud, but the maximum voltage it can deliver depends on the amps ability to deliver current into a load. i.e. Ohms law

V=IR

Where in this case R is the load V is the voltage and I is the current.
Power is then just I*V.

The problem with comparing outputs is manufacturers will tend to quote them where they are most impressive, so unless they are quoted around the same point they are hard to compare directly.
But it most cases it just doesn’t matter, most decent amps will drive most headphones (with exceptions) loud enough to damage you hearing if you really want.

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Is there any way to know when an amp’s output doesn’t scale linearly? For example, most amps, when they do provide more than one output value, might show something like 400 mW at 16Ω and 200 mW at 32Ω. If that’s all the info given, can we assume that the amp will do 20 mW at 320Ω?

Then there’s the Earmen TR-amp which gives specs of 16Ω = 400 mW, 32Ω = 350 mW. Can we predict what its output will be at higher loads? (I’m assuming we’re sticking to the context of only SE or only balanced.)

The reason they stop being linear at some point is they transition from being current limited to voltage limited or vice versa.
There is no way to predict that without knowing the design, or having figures that show it.

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Many thanks!

Ok. So how much diference in power from xrl would it be to buy thx 789 and connect via xrl as an amp and aune s6 pro as dac.
Would it be massive jump in power?
To drive planars like argon mk3 of course via xrl outupt.?