KZ has been steadily refining its hybrid in-ear monitor lineup over the past few years. Where earlier releases often focused on aggressive tunings, more recent models show a specific path and better overall balance. The ZS12 Pro 2 fits well within this newer generation, with a more controlled low end, a cleaner presentation and a stronger sense of space and stage.

The ZS12 Pro 2 combines a dynamic driver with multiple balanced armatures in a configuration that promises clarity, energy and versatility. It leans toward an open and engaging presentation which is meant to work across a wide range of genres.

I was asked by KBEAR to review the ZS12 PRO 2. I wil have a look at the build quality, comfort and most importantly, how do they perform.

Build quality
The KZ ZS12 Pro 2 shells feel lightweight, yet sturdy. The overall build doesn’t feel flimsy, construction quality is well above what you might expect in this price range.

The presentation is basic: a small white box containing the IEMs, a plain cable, a set of ear tips with a good range of sizes. While there aren’t many extras, everything you need is present and functional. For anyone who wants more refinement, upgrading the cable (later) can be a simple way to enhance the experience.

The ZS12 Pro 2 uses a hybrid driver setup with one dynamic driver and five balanced armatures. Rated impedance is 35 ohms and sensitivity is 109 dB. In practice it plays fine from common sources, but it benefits from a competent dongle or DAP. It does not need extreme power, but it sounds more controlled when the source is of good quality.

The shells are light in the ear. The transparent shells give a clear view of the internal layout, it looks neatly put together. There is also a bit of attention to detail inside the shell, which is simply nice to see at this price point.

Fit is comfortable. Isolation is decent, but it depends on which ear-tips you choose. The stock tips can work. Once the seal is right, the ZS12 Pro 2 sits securely and remains pleasant for longer sessions.

Specs

• Drivers: Hybrid design with 1 dynamic driver and 5 balanced armatures per side (1DD + 5BA)
• Impedance: 35 Ω
• Sensitivity: 109 dB ± 2 dB
• Connector type: 0.78 mm 2-pin detachable cable
• Plug: 3.5 mm single-ended
• Cable: Detachable stock cable

Test equipment:

• Mojo2 +Poly
• Shanling UA7
• Shanling M8T
• Campfire Audio Relay Dac

Tested Tracks:

• Sophie Milman - Beautiful Love
• BB King - Riding with the King (Feat Eric Clapton)
• Diana Krall - L.O.V.E
• Loreena McKennit - Marco Polo
• Catherine Russel - Lucille

Sound quality
The ZS12 Pro 2 is tuned around clarity and energy, with a noticeable sense of air. It is not an overly warm or soft sounding set. At the same time, it is not cold or thin in the bass. The overall balance leans towards a moderate U or maybe W shaped. Bass and treble have a little bit more presence than the midrange, vocals stay centred and clear.

It is a IEM set that directly sounds engaging. Attacks are quick and note edges are very clear defined, which helps with separation and keeping busy tracks organised. The ZS12 Pro 2 balances musicality and clarity with a pleasing sense of structure and openness. It sounds detailed, but never crosses the line into analytical territory, staying true to a musical presentation.

Macro presentation in the midrange can feel less clear at times. You hear the micro information easily, but the midrange body is not always clear. Genre matters here. In instrumental music like classical or jazz, the clarity works well. In some vocal recordings, the midrange can feel slightly further back depending on mastering and volume.

The ZS12 Pro 2 never sounds compressed, it has enough headroom to stay composed across different genres. At higher volume the upper midrange can become more noticeable, the sound can feel sharper than intended. Keeping volume reasonable helps.

What stands out, is how unexpectedly musical this set sounds. In my opinion it deserves a better or more luxurious presentation. The ZS12 directly draws you into the music, making it easy to forget the size and simplicity of the package. This level of musicality feels like a pleasant surprise and sets the tone early on.

Treble
Treble is extended, airy and clearly voiced to bring out openness. Cymbals and hi hats are crisp and light. There is good perceived detail in the top end, mainly because the treble energy is present and the presentation stays clean. With bright sources or bright recordings, it might or can sound forward. Sibilance is not fully hidden, if present it is very mild. With warmer sources, the top end is easier to manage. The overall balance becomes more realistic, while still keeping the air and clarity that makes this set stand out.

Midrange
The midrange is clean and transparent. Vocals are well positioned, but not strongly forward. Male vocals feel a bit leaner in body. Female vocals carry just a little more energy. The midrange has good clarity and a decent texture. It does not add extra warmth just for comfort. For jazz and funk, the midrange works well because it keeps instruments decently separated. Micro details sound naturally and the presentation remains clean.

Bass
Bass is really well executed in the the ZS12 Pro 2. It is controlled and responsive. The dynamic driver gives the low end a sense of speed and a good transient behaviour. Sub bass reaches low and provides satisfying rumble. There is only a small roll off and the extension is very good. The bass does not bleed into the mids. Bass sounds natural and energetic, it sounds engaging.

Soundstage and imaging
The soundstage is above average for this segment. It has good width and a great sense of height. Depth is present, but not deeply layered. The stage feels open. Separation is of good quality. The mix does not collapse, even in busy tracks, elements remain distinct without sounding forced apart.

Complex passages can still feel a bit condensed, mainly because the tuning pushes clarity and treble energy. Still, in this price range, the presentation is nice and well above average.

Conclusion
The KZ ZS12 Pro 2 is a budget hybrid that focuses on clarity, openness and a lively presentation. It brings a clean and energetic tuning, supported by a controlled and engaging bass response. It is not aimed at listeners who want a warm, thick and forgiving sound signature. It is more suited to those who enjoy a crisp top end and stage.

Build quality and comfort are very good for the price. The accessory set is sufficient. With the right tips and a sensible source pairing, it performs above expectations in this segment. I really enjoy the sound of these.

Yes, the ZS12 Pro 2 has its limitations. But to fair, in this price range there is not much to complain about. Treble is lively and well-presented, it may come across as a bit forward for sensitive listeners. Sibilance control can vary slightly depending on the recording, it is very slight though. The midrange can feel slightly recessed at times, which can reduce vocal body somewhat. These are tuning choices more than real flaws, but they matter of course, depending on your preferences.

Overall a musical and well-balanced value IEM, offering controlled bass, airy treble and with good separation. Hard to beat in its price category.

Product Page ZS12 Pro 2

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