[13mh13]

The headphone-only amplifier space has had a minor trend toward offering CAREFUL "high" power output on some of their models. It seems that certain hard-to-drive models (or high-Z models) reap sonic benefits at higher "loudspeaker" power.
It's not that headphone transducers require that much power. Rather, the "optimization" may be because the amp has such an easy time driving the load.
Maybe analogous to: Buick 3800 V6 or Chrysler 6.4 Hemi engine in a smaller car.
Of course, this amp strategy must be carefully implemented with disclaimers, CAUTIONS, etc. That said, perhaps the best intro to the topic is here:
https://www.youtube.com/watch?v=YtyCRXizSeM
Several commercial power amps from the 1970s featured a 'PHONES jack.
Example: https://www.hifiengine.com/manual_library/toshiba/sc-m15.shtml
 Looking at the schematics of such power amps reveals what you'd expect: two 220-330 ohm (2-5 watt) resistors in series with the same output as speaker outs.
Essentially, just an adapter -- the kind that have been around for decades.
Since AVA has had history of offering interesting accessories, I was curious whether such a resistor-based amp adapter was one?
If not, is there a best approach? Such as using very high-quality resistors.

[13mh13]

Curious about the OUTPUT IMPEDANCE of most AVA power amps.
They are, like most speaker amps, ideal for low-impedance loads, like 4- or 8-ohms.
But how would an AVA amp react (literally, X)  to, say, 600-ohms?

https://en.wikipedia.org/wiki/Electrical_reactance

[ceylon]

i been thinkin about that for a good while. curious about this in general.

[gammi]

I will be using my M225 monoblocks to drive many different headphones when they arrive. I often use my 100wpc AVR or 48wpc tube amp to drive headphones just fine. I simply connect via an XLR to banana plug adapter.
Hifiman does make an adapter that changes impedance but that's only needed for very inefficient headphones.
https://store.hifiman.com/index.php/he-adapter.html