Ya know, I JUST read about the THX Onyx a couple weeks ago, but was waiting for Amazon to carry it, which it still isn't as of yet. Once it does though, I had fully planned to add it to my list on there! lolCheck the THX onyx and the Shanling UA2, these are even more powerful and have the same format
Yes of course, I'd rather have a neutral dynamic headphone than a v-shaped planar for instance. But if you spend a few hundreds/thousands in a headphone, I guess you can check other criterias besides frequency response. There's plenty of choice.
The max power output is rated at 180mW into 22 ohms. VERY impressive for a dongle! I think the FR is 20Hz - 20kHz, as per this page (feel free to let me know if it's not).
I'd tried out the Shanling M0 BT amp/DAC a while back. It was pretty good, though not powerful enough for 250 ohm DT-1770 back then. Nice device though. The UA2 also isn't on Amazon, which is prob why I wasn't aware of it 'til now. But specs look impressive for it! (125mW @ 32 ohms when using the 3.5mm connector, and 20Hz - 50kHz.)
Yeah I'd def go with one of those two. Though there may be benefits with having dual DACs (iBasso) or a wider FR (Audiolab) with regards to sound quality vs. volume, the Shanling UA2 still has them beat b/c you can buy one for about $100, where with the Onyx you'd have to spend $200, and if you convert the 22 ohms on the Onyx to 32, I'm guessing it's pretty close to the UA2's 125mW @ 32 ohms volume max, though maybe still louder. The Onyx also has an upgraded DAC vs. the Shanling, with both being Sabre DACs.
For me anyway, I'd prob just go with the UA2. Not really sure if the better DAC on the Onyx is worth another $100, even if it can(?) get a tad louder.