Uhm, GR07 does *not* improve. No really. Mine have more than 1k hours on them.
Just try them out. You may be surprised. I find the midbass of the GR07 to be ruler flat, and the sub-bass to exceed most other non-bass oriented phones out there, producing wicked rumble when called for. As for sibilance, I just don't experience it much on my pair. It's sounds like you need some an ER4S or something lighter...
PM me if you want me to proxy the meelec tips to you.
Actually GR07 have ok subbass down to 40 Hz, then it drops pretty sharp. Yes, I'm demanding there.
The problem is the resonance from the silicone tips I think - with the foam tips the mid bass is less pronounced, but I can't find long enough foams that fit, and the short small ones tend to either lose fit or collapse.
In fact, they fit best with the included medium (or was that small?) silicone. (which is quite sleek)
Well, I have tried:
1) UE triple flanges (w/ RE272) 2) Hifiman triple flanges (w/ RE272, worked kinda almost - was abrasive though)
3) Sleek Audio triple flanges (w/ SA-6, nice fit but the IEM itself is lacking) 4) Etymoic triple flanges (w/ SA-6, too hard, didn't bend enough)
None of the triple flanges fit GR07.
Also, I have tried various Comply tips, comfortable, but too short. When I forced the Comply P on, they soaked so much treble it's not even funny, but the bass went nice, linear and better controlled. (I bet the too small nozzle was the cause of the lowpass.)
I have some hope that Monster gel tips would work. Is that plausible?
The problem is that my ear canal has a bent shape at the start. Have a peek:
http://ompldr.org/vZG9kMQ/IMG_20120509_083936_marked.jpg
http://ompldr.org/vZG9kMg/IMG_20120509_083945_marked.jpg
http://ompldr.org/vZG9kMA/IMG_20120509_083402_marked.jpg
Those are Spiral Ear SE-5 Reference. Expensive, superb quality, bass pretty much outstripping most dynamics, but suprisingly balanced pretty bright - and they're not as comfortable as I hoped. Also they look funky in ear, like a hearing aid, not easy to put in or take out, so definitely not good for portable use. Great for anything else though.
(Don't mind the green markings, the areas that are to be corrected - I'll have to get new impressions anyway.
Hint for producers: ask for impressions *after* you order parts, heck, even with pre-pay. When made, these were already 3 months old!)
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I forgot to say what's the balance I'm looking for. Beyerdynamic DT-1350 is pretty much great balance, I'd only like a tinge more subbass off them, maybe fewer high end peaks. See, flat bass is just not musical for headphones.
To show you what I mean, that's the final correction curve for those DT-1350: (500 Hz reference)