Bass comparison? What? There's no comparison to be made. Everyone knows that the K70x have NO bass at all.

FWIW, last summer I compared my newish K702 with an older, broken in, K701, and they sounded quite different. From what I recall, the K701 had a wider soundstage and somewhat fuller lows, while the K702 was a bit more detailed. Still find mine a tad too forward in the upper midrange/lower treble. Not the most forgiving headphone on a harsh recording.