The TK8iE’s sound is sometimes brilliant, sometimes boring, but always impressive.
First the brilliant: its powerful, textured lows balanced against extended, texture-rich highs on taut mids. Lows yawn out high-pressure detail from the almost inaudible opening seconds of Markus Schulz’s Mainstage whilst spinning bright highs, and full, if dry-tipped, mids. If you’re a basshead dying for a high-end earphone, the AKT8iE might do it for you. That is, as long as you don’t like flab.
Despite digging low, bass keeps its place. Positionally, it throbs most at the sides of the head, with a central anchor at the base of the neck. It is fast, immune to flutter, and makes residue-less translations to mids even whilst cleanly spitting out the fastest EDM and trance. In the earphone world, it has few to no competitors capable of maintaining as detailed a mid section in the face of Empire of Hearts’s throbbing bottom-end. Along its leading edges is a slight metallic tinge, which may help the AKT8iE mkii’s bass sound tauter than it is.
From memory, the mki version humped the mid bass too much. This marginally gummed up the to-mids transition zone. Three Fujiya Avic Headphone Shows ago, that was the only thing about which I had to whinge. My memory could be faulty. If it is, I apologise. If not, mkii has fixed the only fault I perceived in the mki.
Wide-band mids are equally high-pressure, but they lack the metallic tinge of upper bass and upper mids / lower highs and therefore attract less slightly less attention. Bass/treble heavy music genres: trance and progressive, metal, etc., draw focus to lows and highs. This may be part of what delineates instruments so well. The TK8iE describes instrument niches very well; certainly better than most single-dynamic earphones I’ve heard. It’s not as scalpel-like as Ocharaku’s Sakura Plus – nor is at as pulpy -, but it’s not far off. It relentlessly upholds dynamics better than Sakura Plus, whose highs can veil higher-voiced midrange elements.
Sakura Plus also describes a wider and deeper stereo image. The TK8iE’s stage is rounder than it is wide, and far more compact than any Ocharaku FLAT4, whose sound stage is truly an out-of-head miracle. In comparison, the TK8iE’s stage describes a gentle arc in front of the head which extends almost to the shoulders before dipping in again from there. Full, round, and positionally accurate, it reminds me of a good close-range 2,1 system. Space between instruments is clear.
The AKT8iE’s highs are clear, forward, and textured. Their slightly metallic edges aren’t harsh, but can exacerbates jitter and distortion in problematic players and DACs. They aren’t tripped up like the ER4 to model the ear’s sensitivity curves. Their metallic edge leads clean and airy percussion with fast decay.
Unfortunately, the AKT8iE mkii is more sensitive than its spec suggests. It reveals a lot of hiss from Astell&Kern’s XB10, a bit of hiss from their AK70, and nominal hiss from an iPhone 6. Naturally, you’ll hear hiss from a lot of desktop sources, on both the high and low end.
[update] If you had a hundred or so bones left in your budget, Campfire Audio’s Andromeda is an interesting companion. Particularly because its highs carry similar sound pressure, but with softer edges. Where the AKT8iE errs metallic, Andromeda errs organic. The AKT8iE reveals problematic THD and jitter more readily, but it fits more solidly in the ear and feels way way better. And the AKT8iE’s bass, while not deeper, hits more like a speaker. If Andromeda were as comfy, it would be hard to as handily recommend the AKT8iE over it. But for me, comfory comes first.
I hope that the mkii holds up to the daily grind better than the mki appears to have. The latest TK8iE mkii is one of the best-sounding, most dynamic earphones I’ve ever had in my ears. And it is even more comfortable than it is good sounding. Its over-engineered accessories are completely forgivable in light of its incredible sound and fit. It’s a concession to which I give full, unbridled consent.