Are you sure? because my dt 770's can be pretty loud, i'm using them in combination with an emu 0404 soundcard though... I always thought they had an impedance of around 80 Ohm
Edit: never mind, i should really hang out with my gear more often: I just realised I have an DT770 Pro
![Rolling Eyes :roll:](./images/smilies/icon_rolleyes.gif)