Pros: Sound Quality, Build Quality, Android Compatibility, Chocolate Smell
Impedance: 12Ω-16Ω (depending on the version, 2.0 vs 2.1)
Cable length: 1.2m
Plug Type: 3.5mm gold-plate
Rated Power: 5-20mW
Frequency Range: 20-20000Hz
I've got my pair from Xiaomiworld, and it's an original one. It seems mine is the 2.0 version, but it was shipped by the end of January, so the ones sold now should be the seemingly newer 2.1 version. They also carry the newer IF version. Anyway, this seller carries the real one, so no need to worry about fake pairs. Their service and communication is pretty good too.
Here're the links:
And for IF version:
Sound signature maybe not be far from a consumer-friendly V-shaped one. But as for sound quality, that's another story.
Before getting to describe the sound characteristics, let me just say that this Piston new model doesn't sound as what'd be expected from a $20-30 earphone at all. It simply competes with the best earphones I've listened to in the $50-70 price bracket.
The Piston 2.0 presents a typical customer friendly V-shaped response. Extension is quite good on both ends, giving a pretty wide soundstage and sense of space. The low end is quite prominent and rather dominant over the rest of the frequencies, and (fortunately) while it may not be considered as a heavy-bassy earphone, it should be enough for the bass listeners. Despite the strong nature, both sub and mid-bass are very detailed and well controlled, with a noticeable added mid-bass hump for some extra 'fun' factor.
Similarly, the top end is very present without any annoying peaks, and rather linear on its whole, but not overly smoothed or even rolled-off. While the treble won't have the same authority as the bass, it won't lack in sparkle and crispiness.
As for the midrange, here's where I have mixed feelings. On the one hand, the mids are really well detailed and airy, and pretty much clean from unnecessarily extra bass bleed. Separation is also quite amazing both in the instruments and vocal dept. In fact, the vocal separation is really surprising, not only for a V-shaped $20-30 phone, but even beats mid-centered IEMs when it to comes to separation.
On the other hand, as impressive as the midrange is, it isn't safe from the common V-shaped effects. While it's not lost in the presentation, it does feel rather cold and distant, and sometimes slightly veiled. Vocals lack texture and sweetness, too. That said, some extra EQ can help in this regard, but still may not fit for the mids lovers.
Yet, the overall detail is much more than what would be expected from this price and matches some of the best sounding in-ears I've owned within the $50-80 bracket.
Perhaps I'd rank the Piston 2 around the Vsonic VSD1-S level (even though the signatures are quite the opposite of each other) and a bit better than the RHA MA350 in detail and smoothness (but personally could prefer the RHA midrange richness over the Xiaomi's).
The Moe SS01, for example, are better in most aspects, but the Piston aren't too far from them.