Sorry for all these mini updates, but I feel like talking about the HD-650 I just got in.
From my main (best) setup the sub-bass is MUCH more present and more extended than my 598, 600, 580 and Q701. No doubt. I actually expected it to be the same as the HD-600, but it's not. The sub-bass is as present as my DJ100 (I won't go there!), which makes me very, very happy.
The HD-650 seems "fairly dark" on my Micro Amp. Just kind of how it should sound. Not really, but only compared to the HD-600 and my Q701 (well, duh). Here's what's interesting..I find the Fiio E9 for whatever reason to be kind of a bit treble happy. I mean still fairly neutral, but it seems to give all my headphones what seems like a tad more treble. I just saw some measurements for my amp and it's not rolled off in the treble. I think for those that find the HD-650 to be too dark, the E9 might be just the ticket. I bet the E7+E9 was made and tested with the 650 in mind. Call me crazy if you want!
This song below (crappy youtube quality, I have it in FLAC) was very congested sounding on my old HD-650. Some bass bleed and didn't sound good at all. I think it's a warm recording and you can tell with this song that the HD-650 has a tad less treble than on many of my other headphones. Not that I care! Still good. Anyway, the sound doesn't sound as bad now. Very good. It does add a bit of warmth to the recording, but otherwise accurate.
There is actually low-bass in this recording! Stuff that's barely registering on my Q701, but is there on only my KRK KNS-8400, DJ100 and a tiny bit on the HD-600.
I still get an impression that the HD-650 sounds like it has a better soundstage than the HD-600 (smaller perhaps) and with more of those tiny details. Even how you feel as if you know what type of room the recording is made in! No lack of detail here.
BTW I feel that Canare or Mogami might degrade the sound slightly due to extra warmth from their high capacitance. I got that impression last year. I love Mogami with my 598 and Q701 though. Don't bother lecturing me over a $3 cable.
Not that anyone cares, but the Micro Amp sounds a bit more flat than the E9. Both still measure flat (not 100% sure if the E9 does), but that doesn't mean much. The E9 sounds thinner in the mids. With the Micro there is a touch more warmth. It's not a warm amp to me AT ALL. Like maybe the warmth of a Clip+. Yeah...I never knew the Clip+ had even remotely any warmth
This amp doesn't add much of any coloration to anything I can detect.
Oh yeah.. the lower mids certainly seem forward on the HD-650 (on any setup). Well, some area of the mids. Guessing it's lower mids because the upper mids are supposed to be neutral or recessed right?
Another thing...this HD-650 (at least this pair) has similar bass quantity as my DJ100 (which some say is bass light!).
I also remember that with my last pair the 650 didn't seem too dark until I used them with gaming.
The lower mids of this 650 definitely seem more forward than those of the Q701 and basically all my headphones. I must be ultra sensitive to lower mids. Is that possible?!
edit 500: I thought any more warmth than what the HD-600 has would ruin the sound of a headphone. Boy, was I ever wrong. The really full mids of the HD-650 sure are nice. No bloated bass here yet. When it sounds that way it's due to the recording (so far!). I can verify this on other headphones.
