If you need mix and tune the sound, maybe considering closed back version hd560 which is hd400 pro? Just need to replace the 3m long coiled cable with straight cable, or the stock cable would add too much weight to your head. hd 5 series (225g without cable) feels quite bit lighter than hd 6 series (260g). audio technica's r70x is on par with hd600 in terms audio quality and tonlity, but remain the lightest (210g), though the small earcup will be a trouble if your ear is too big to fit inside the cup.
If you need mix and tune the sound, maybe considering closed back version hd560 which is hd400 pro? Just need to replace the 3m long coiled cable with straight cable, or the stock cable would add too much weight to your head. hd 5 series (225g without cable) feels quite bit lighter than hd 6 series (260g). audio technica's r70x is on par with hd600 in terms audio quality and tonlity, but remain the lightest (210g), though the small earcup will be a trouble if your ear is too big to fit inside the cup.