Hi all,
I'm currently auditioning a demo unit of the AS-2s - just thought I'd share some thoughts. I don't have the depth of experience that members like ericp10 and FlySweep have, so I'd think their opinions should carry more weight. Anyways, here's a short comparison of the AS-2s vs. my current favorite IEM, the GR07 Mk II:
Overall, the signatures of these are very very close; this is a good thing for me, as I picked the GR07s over all the other IEMs I've had the fortune to hear (check my profile for a list of almost everything I've heard; I've also briefly auditioned the Ortofon EQ-5, Brainwavz B2 and Hisound Crystal). The bass of the AS-2s hits lower than the GR07s, if you can believe it - making everything sound just that much sharper. I'd previously found the GR07s the kings of sub-bass, but the AS-2 is clearly better in this regard. The mids of the AS-2s sound very much in line with the bass and the treble - a little more forward than the GR07s I think, but it's very close. The treble of the AS-2s sounds very technically competent - I'm not a huge treblehead but they do seem slightly better than the GR07s here - certainly a bit less fatiguing. I'd guess it's missing some of those peaks in the upper registers of the GR07s, but I'll leave it to more experienced members to corroborate that.
The separation on the AS-2s is clearly better than the GR07s as well - if audio memory serves, they aren't far from the UM3X here. Also, I finally see what eke2k6 means with respect to the GR07's soundstage - it really is height that they're missing, which the AS-2 isn't. Consequently, it certainly sounds more open and well-rounded than the (now in my mind) squished GR07. The AS-2s are more efficient as well, requiring about a 5 step lower volume level than the Vsonics out of my Clip Zip - which by the way drives them just fine. I do hope to experiment with some better sources at some point.
If I had to pick one word to describe the AS-2s, it would be: natural. Everything sounds great on these - the timbre is great, and I'm pretty confident the dynamics are improved over the GR07 as well. It sounds very cohesive as well - I can't pinpoint any difference between the sound of the dynamic driver and the balanced armatures; I won't pretend to be an expert in this area however.
Now for the main question: are these improvements worth a ~$350 premium (my other option is getting custom tips for my GR07s)? I have yet to fully figure that out, but I'm leaning towards ordering a pair.
If anyone has any specific questions, or any tracks they'd like me to listen to with these and provide feedback - I'm happy to do that. I'll be going on vacation starting Friday morning however, so won't be able to listen to these after that.