[TMRaven]

Dark's a tricky word.  While it is probably the correct word to use for the HE-400, dark usually gets associated with overly bloated and bassy headphones with virtually no presence in the mids and highs and a far from clear sound altogether.  HE-400 however, is extremely clear, and the more you get used to its signature the more neutral it will sound.  Judging by your fatigue comment on the HD-25 I don't think you'll mind their dark signature too much.  I've owned the DT990 (famously bright) and never thought of the D2000 as overly fatiguing and even I can greatly appreciate the HE-400's overall presentation.  I said the same thing about HD650 vs D2000, but I'll say it here again.  9 times out of 10 the 'warmer' sounding HE-400 makes the D2000 (and probably your HD25) seem veiled in comparison.
 
 

 

[MalVeauX]

 
Quote:

Is the HE400 balanced enough to run other types of music? I did hear those cans being a bit dark.

Also could either of you compare the HE400s with the Ultrasone Pro 2900s? (or 900s since the drivers seem to be the same)

 
Heya,
 
The HE400 is great for all genres. It's not dark at all. It has a touch of brightness to it even, a sparkle. It's actually a balanced headphone, simply has a nice deep extension into bass making it warm and able to satisfy someone who craves a little more bass in their life. The mids are awesome. The treble has a touch of sparkle. Very well detailed, great control and texture, great speed, great extension. It's a really good headphone.
 
I don't have a PRO2900 to compare to. However, I do the PRO900 & HFI2400. If the HFI2400 is any indication of Ultrasone with openback, it's good, but overall the HE400 bests both in mids by far, has smoother treble, and packs a lot more sub-bass than the HFI2400 does, with way more control. I find the open versions of Ultrasones have good mids and smoother treble than their closed counterparts, but they pay the price by losing some of that sub-bass. The HE400 does it without the loss in sub-bass which is awesome.
 
Very best,