read whole thread, here my POV
just bought xense set, initially i wasnt impressed at all, well nothing outstanding, was listening to AKG-K240 (55ohm version) studio past 5 years, those died recently
i changed opamps chips to LME42..20 something, they costed like 10eur, seriously guys, comparining to ANYTHING, after upgrade xense set
KILLS anything I ve ever heard, those 10 eur was for me unimaginable sound upgrade hehe, as big as from 10eur panasonics to AKG's or even better.
whole soundstage opened, bass is supertight and strong, highs clear and eteric, just plain WOW, worth every cent.
though havent heard anything with impendance higher than 60 and amplified before (heard grado sr60 not i version, disliked it).
just thinking about getting sennheisers hd800, seriously would it be any difference? (got almost infinite funding source, so money isnt a problem), akg 240s didnt sound any better after opamp upgrade, i mean not any significant