Agree with your comment
-25hours of burn-in, this is third session I put AST on, for well over 4 hours
-compared to benchmark fully burned-in qdc Anole VX and my reference IEM for monitoring: Softears RSV. So that it’s not my brain-burn in as I have clearly comparable scale next to AST
-Treble is the speciality of AST; great sensation of warm and calm tuning with astonishing detail retrieval that can well expected from properly tuned multi-BA, the open vent 6 packs of missile launcher-ish tweeter unit indeed is some interesting gimmick that KZ came up with, this is why I’m sticking with KZ even with series of “painful
spiked extreme house V-tuning” experiences. Some R&D taking place and it works!
-Mid, uppe-mid is OK, I could use a bit lifted 3khz pinna gain area, but I was able to find my comfortable tuning with SpinFit Cp100+(known as vocal booster) & DAP’s low-pass filter in Short delay Sharp Roll-off mode(which I don’t usually use) to have piano&vocals show clarity
-Bass is another “wow” factor of AST, well controlled, good texture, the weakness of BA bass (plain and lacks impact) seemed blurred by simply amp its to taunami class massive quantity —which works
-Thanks to multi BA, the elevated bass does not totally overshadow mid/treble, as the other range also has some presence
-I’m now more confident to refer AST is power hungry IEM, (similary to ASX, but much more power-thirsty than ASX); this could divide impressions to day and night,
With less powered source:
one may say “ahh it sound muddy, everything is off focus, with one note bass “boom”
With high powered source:
one may say “it’s the one of the best sub $300, specialized in resolution/ brain shaking bass / hard to attain multi-layering capability which only kilo buck 8+BA IEMs could offer.
I think AST is well worth $100 tag, and compared to $129 monster TRI Starsea(it hits A- in my list), AST still can justify its raison detre by layering / separation and impactful bass.
compared to $169 widely proclaimed best-value-to-money See Audio Yume(I could only rate Yume to C+, A+ for tuning but technically C-), AST is well above Yume in terms technicality, tuning is personal flavor so I’d leave it. AST still can justify @ $169
compared to $299 Mangird Tea / $319 Moondrop Blessing2/ $330 Moondrop Blessing2 Dusk: I can still justify AST for multi-layering for music with complex composition, but overall I found Tea/ Blessing2/ Dusk a little better made, like 10% better if pulling out a number.