Those solutions are too pricey for me. I am just going to load Equalizer APO and pair it with a Chord Hugo 2 and USB to my laptop. I want to see if I can make my Sennheiser HD800S sound good with the Chord Hugo 2. If I can't, I'll just purchase a pair of Focal Clear headphones.Auralic Aries G1 streamer has a parametric EQ - I Belive it can be adjusted via a web browser link and or Mobile phone / tablet
Roon has a parametric EQ, which I have tried, the user interface is clunky, you cant hear changes instantly. But like @HiFiHawaii808 I dont really want to add a computer to my rig, right now I have a laptop open and a super thick / ugly USB cable trailing across the living room floor - I am looking for a mobile controlled phone solution)
Weiss DAC 501 with network streaming has parametric EQ but is very $$$. Weiss is a band known for use in mastering and very high end recording studios. I expect that to have very tweak-able parametric / room correction as part of its (very interestingly featured) DSP section.
Node 2 has a very workable bass and treble equaliser - it can get you a smile curve / v shape that many people like and will keep most people happy. Its a great product at an amazing price.
My normal headphone system doesn't need equalization. I like the current sound. A Loki would be all I need if anything at this time. Someone needs to create a parametric 10 band hardware equalizer for under $500.