[Snoochers]

Isn't my AVR receiver an amp though?

 

[Monsterzero]

Yes it is,but now were circling back to the beginning of this thread.

Modern receivers headphone outs are typically afterthoughts,so when you start talking about headphones that require more than a potato to drive it,youre taking a risk that it may or may not sound good thru your headphone out of your Onkyo.

EDIT: I really cant advise you any more than I already have.At the end of the day I dont own your exact receiver.I do own a NAD receiver made in 2014 that was more than twice the price of your Onkyo and it cannot drive too many of my headphones well,so all my thoughts and comments are based upon my personal experience.

Perhaps your Onkyo has a superior headphone out to my NAD. I dunno.

One last thing to consider,my 800.00 NAD receiver driving my LCD-2s sounds like absolute dirt...when i take the same headphone and plug them into my 99.00 Schiit Magni Uber they sound great,not quite as good as thru my Sansui,but still very good.

Again my final suggestion is to buy the HD650,try it thru your Onkyo and if youre happy with the results that is all that matters.

If youre not happy there is a plethora of cables/converters/switchers available that most likely will be able to work within your system where you can add a small but powerful dedicated headphone amp.

Please let us know how it turns out...im quite curious.

 

[PurpleAngel]

Thanks guys. Indeed I think the zone 2 does not output from digital inputs (HDMI), so that wouldn't work. Perhaps I can do USB or HDMI or something. I'll figure it out.

Ok.... maybe I won't get HD650s because might be a bit of a fuss. Perhaps I can get something easier to drive like Hifiman HE400i. But the impedance on those is around 35 I think and my impression is that the impedance of the headphones needs to be at least 8 times greater than the output impedance ? With those it would almost be 1:1 if using the receiver jack...

 
The 8 times impedance issue is more like a nice guideline then a rule.
I plug my 40-Ohm headphones into an amplifier with a 10-Ohm output impedance and the 40-Ohm headphones sound good.
For use with a modern receiver, I would push people to get headphones in the 250-Ohm to 300-ohm range.