Yes. Plenty of volume for the HD600, even with lots of negative pre amp to EQ the bass up to Harman.
No. Both devices are flat (without sound character).
Thank you, exactly why I am looking at the amp because with my Sonarworks EQ it adds a much needed bass bump but then subtracts allot of headroom to avoid clipping. I almost max out my volume most of the time and am also a bit concerned this is affecting transparency in the bass (having more headroom is the other motivation).
Flat response is exactly what I'm looking for when mixing (the sonarworks boost is said to bring the hd600 "closer to flat" below 100hz apparently)
Realistically, no it shouldn't make a big or noticeable difference. L30 should do fine though

my amp is an A20h and I don't even need to go over low gain for my HD600, just to illustrate that their power requirements are a bit exaggerated..
Thank you good to know, I am aware of the "classic diminishing returns" that I am chasing but on the off chance it does make a difference I'll give it a shot.
Hearing allot that the HD600 scale well with a good amp and I've been wanting to try it out for a while. This DX1 looks like a great value, closer to the Topping L30II than I can find anywhere at this price point (also I already sold the scarlett since I don't use any mic inputs whatsoever, but now I am missing my volume knob lol).
Guess even a small improvement in transients or any definition will be an added bonus! Nice amp btw!
Thanks!