Hm... I do not get the impression of Edition 9 bass being obscenely strong, more so I had another head-fier try it at my place and he replied that he heard far less bass than he expected after all the impressions. Might be pecularities of individual systems/recordings.
Proline 2500 vs Edition 9: I was waiting for the people to cool down a bit on head-fi, more knowledge to be acquired before I take on sovkiller with this hah, then as I was about to post this, head-fi went to the apocalypse... This is the same headphone, no doubts about it. You have to listen a bit more carefully here, but they are incredibly identical. The only difference is that on one the frequencies are shifted towards treble, while the latter is shifted towards bassier, softer sound - basically tuning the tonality by changing the chassis. In all other respects, including extension - the cans are identical.
I don't think this is very obvious, but if you listen to how these cans interpret individual notes, or more so percussion - it becomes fairly obvious.
- Cheers. I sold my Edition 9 for one idiotic reason (apart from buying speakers) -> the bass on it is too much for me, same reason I could never use an HD650.