[Mad Lust Envy]

The HE400 has somewhat of an identity crisis. It is a dark/warm headphone up until you hit its treble, which is anything but smooth/dark. The treble is quite sparkly and emphasized. The K702 Annie stays warm/smooth throughout the whole audio spectrum, though the bass and mids arent as dark as the HE400s.

 

[Chris J]

What do great mids sound like?

They sound like Electrostatic loudspeakers.

Try listening to a pair of MartinLogan loudspeakers, make sure they are a model equipped with an Electrostatic Panel and a "standard" woofer.
They also make a full range Electrostatic, but it is priced somewhere north of $20,000

 

[Overwerk]

I have done a serious research without going too deep into it, my preliminary conclusion is that bass perception is weak in human due to evolutionary reasons, therefore enhanced bass appeal to humans, except that is not how music really sounds, it's just how defective human sound perception system works. It's like when you hear yourself and part of the sound got distorted when it enters your ear, and when you actually listen to the recording, it is how the recording equipment perceives your voice, which, depending on the quality can be different and obviously can be very different from what you hear when you talk to yourself. 
 
I totally and whole heartedly stand against the undisputed(among those that know better) truth that if you call yourself an audiophile, you know better to act like them girls in parties and clubs who knows nothing about music more than mindlessly moving and bobbing to "da beat", or, that the Beats by Dre are equivalent of good expensive headphones. You know better to stay away from the urge to bang your already bass deaf ears with more bass, making it even worse at perceiving bass as it is.