More bass = less mids or treble
and so forth...
In the case of the HE-400 pleather vs velour
Velour = more upper mids, meaning that to our ears, something else isn't as pronounced, even if it's technically the same. That can either be less perceived bass, or less perceived treble. Some are saying less bass. That is understandable, though it's actually the same bass as before, just the upper mids are meeting up with the bass. Some say less perceived treble glare. That is also understandable, as the transition from mids to treble isn't as steep.
It really depends on what your ears are focusing on. Either way, the main change is the upper mids. If you change your volume to volume match the upper mids of the pleather vs velour... the pleather will sound both more bassy and sharper on the treble.
Because the upper mids are so recessed on the HE-400's pleather, I can totally see why some of you say the pleather has more bass. You're compensating the lack of upper mids with volume. I'm surprised the treble isn't destroying your ears.
I've heard the HE-400 enough. I owned it twice. There is no comparison to me. The pleather is a mess next to the velour, but if a mask of veil is what you like, then yes, the pleather is easier on the ears. Everything is more muddy on the pleather.
Edited by Mad Lust Envy - 10/13/13 at 12:59am