I actually played around with this some more and kinda figured it out.
There is a significant improvement playing EQ with the EAX and A3D effects enabled. It turns out it is somewhat hardware dependent, and my theory on my Corsair Void Pro headset messing things up was correct, as it isn't EAX and A3D compliant by itself. I plugged in my old Sound Blaster Live 24-bit USB External with some average stereo headphones and it was night and day. Additionally, with 3D Sound Back from Realtek (
https://www.guru3d.com/files-details...ck-beta-1.html), Creative ALchemy, or the DSOAL above, you can have this effect on any Creative, ASUS, or Realtek audio hardware and hear EQ the way it was meant to be (or as close to it as we are going to get).
If you want to go further for other titles (as the Realtek solutions only go up to EAX2, which is fine for EQ), there are modded drivers that give Creative Soundblaster functions to most Realtek HD Audio chipsets, but that's a whole other beast to slay.
But yeah, so far it sounds pretty rad.
P.S. I even messed around with the BassMIDI fork Omni MIDI versus the solutions in the MIDI thread with some significant improvements:
https://github.com/KeppySoftware/OmniMIDI/releases