Oh yeah I'm definitely not likening the HF-580's sub-bass response to the HD650, they are very different there, where the HF-580 also has slightly elevated bass response and better extension, while being slightly less mid forward.I've got no experience with the HF-580 but the HD650 does definitely has less subbass impact compared to the X2s (although they also have mostly midbass) and it doesn't offer a wide soundstage either. I think the op need to tell us more about what he's looking for to get better help.
It's not a super technically proficient planar driver either apparently, so the HD650 probably sits slightly ahead in that respect.
EDIT: Crinacle has some graphs that kind of highlight this difference
You can see here two headphones that use the same driver as the HF-580, along with the Harman target and the HD650 all against a base line of a flat response.
The HF-580 is something of a budget frankenstein of three of these: it's simiar to the Blon's bass response but closes in on the Harman target due to it being lifted, and the similarities flow into the lower mids; the patchiness in the rest of the mid-range more resembles the Aiva, and then the treble tends to resemble the Blon again.
Here's some other measurements showing similar attributes, but with the stock cloth pads on the HF-580 (when its bass is at its weakest):
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