I'll defer to
@jinxy245's reply about the bass issue (I agree w/every word). I would add 1 comment: I have an OTL tube amp (Woo WA3). I love the Aeolus' sound on it. But there's little doubt I get somewhat deeper, more impactful Aeolus bass on SS amps. There are many wonderful things about tubes, but barring endgame/big tube amps, tubes can't usually equal SS in bass power.
I've owned a couple borderline basshead headphones, perhaps "better" in certain ways than the Aeolus. But IMO the bass of this headphone, like every other part of the frequency spectrum, is highly musical. I never feel a lack of bass w/my Aeolus, never find myself wanting something better/different.
I owned a rather beautiful padauk Eikon until a few months ago. Only sold it because closed back designs in general tend to exacarrbate my tinnitus & migraine. Just wanted to say that I greatly admire the Eikon & think of it often: it's one of the most dynamic, rousing headphones I ever heard. The bass is borderline sensational (incl. real sub-bass).
- My point is these headphones sound rather different and are equally worth owning.
Another comment is that unlike the Eikon, for which few tried & true pad options exist, the Aeolus has 3 or 4 recommended pad options (my favorite is perforated suede universe; 2nd fave is Verite pads). Choice of pads, as well as seal, affect the bass you get from the Aeolus.