This is pretty accurate. I'd add:
LCD 2.2 >> HE-400 > HE-500 > (marginally) HE -560 > HD800
The bass difference between my HE-500 and HE-560 is subtle and only around 30hz and under the HE-500 has slightly more rumble. HE-500 also has a bit more punch to the bass, but the HE-560 has a bit more clarity and sounds more open.
The HE-560 bass does have a bit better clarity, although I'm not sure if this is mostly because it has slightly less rumble.
The HE-500 is slightly more 'fun' due to a bit more punch and sub bass and the HE-560 a bit more open and refined.
Honestly, you'd have to swap both headphones back and forth and volume match perfectly to be able to tell these differences. Listening to just one w/o the other they sound really similar.
The comfort & weight difference is massive however.
After more listening i have to take some of this back. I think the HE-560 is equal to HE-500 in bass not less. The reason it's hard to gauge is because I need to turn the volume way up on the HE-560 compared to the HE-500 so when I swap to compare, either the HE-560 immediately sounds too thin or the HE-500 is much louder. Once I more carefully volume match it's clear the HE-560 bass is just as powerful.
The mids and treble on the HE-560 are perfect as well. The detailing, textures, separation all around is just amazing for electronic music - which is mostly what I listen to.
Overall the headphone has an extremely balanced, open and refined sound. I'm really happy with it.
Edited by moshen - 7/12/14 at 12:46am