Meanwhile, I'm trying to see if I can find a place that would let me demo the HE-400 and HE-500. I'm down to these two headphones but I'm not sure which one I would prefer in terms of sound sig. I find myself wanting more bass than my current iems/headphones, so the 400 seems solid, but the 500 is universally praised. Anyway, I'm tired of reviews! I wanna listen myself!
Always best to hear for yourself.
FWIW, for me the bass was the weakest link in the HE-500's sound sig. I prefer the HE-400's bass. Actually, I just prefer the HE-400 period. Though both are pretty solid.