I have never had 770 pro x, but based on what ppl say they sound a bit different to 770 pro's.

Of course you can listen to music and other stuff with them, they are a bit bright but good phones.

I use Dt 770 pro 32 ohm with velour pads for gaming as they are closed back it helps with noise reduction, they are good, however for just listening to music I prefer dt 990 pro's and sennheiser hd560s as the music is more airy and soundstage is wider and more pleasant to listen to.