Yes, I’ve tried it out (briefly). It’s definitely an improvement in the treble, but I prefer the lower end the way it is naturally. I’ve tried to modify it a bit, but haven’t entirely succeeded yet. One good thing is that the EQ seems to change the soundstage of the NDH very little.

I’ll definitely have to look into EQing the HD 800 as well when I get around to trying it more. Oratory‘s presets are usually a good starting point for me.