Just recently purchased a pair of HE-400 from a fellow headfier. I'm really enjoying them especially the low end. My only grip is I find that the treble is a bit too harsh. I'm unsure if this has to do with the source I'm using or if it has to do with the headphones sound signature. I thought I had gotten used to bright treble with the DT 990, but after listening to this headphone for about 3-4 hours straight, I'm still finding the treble a bit sibilant (I'm currently EQ the high end just too be able to enjoy my music).
Currently running it straight from my Macbook Pro. Any thoughts, advice, personal experience would be much appreciated.
I felt the same. The DT990 has strong treble, but it's clean. I find the HE400's treble to be more jarring at times.