KZ AS24 Review

KZ AS24 Review

KZ AS24 Review – 12BA Drivers Per Side

KZ has recently launched a new offering – the KZ A24 – which boasts an array of impressive attributes. The A24 is available in two versions. The price difference between them is not that big. But if you are a person with your style preferences, the Tunable version is a very good one to try.

KZ AS24 Review

The A24 has 12 BA drivers per side, which breaks the audio hardware ceiling. 31736 array-design BA is responsible for high and ultra-high frequencies. Customized 29689 BA is responsible for mid-frequency. 30019 BA is responsible for high-frequency. And the newly designed 22955 BA is responsible for low frequency.

KZ AS24 Review

KZ has designed a “trident” reed inside the BA driver specifically for HiFi earphones, which is more accurately centered between the magnets. The traditional “u” shaped reed is designed for hearing aids, and its bending process may lead to poor stability and consistency. KZ’s trident reed design can enhance sound density, reduce distortion, and achieve better transient performance. Compared to all previously balanced armatures, the newly designed 22955 BA can deliver more powerful and resilient bass. The new generation 29689 BA can deliver spacious, elegant, and natural sound with superior treble extension.

KZ AS24 Review

A24 has dual tuners and 8 switches. There is one tuner on the top and one on the outside of the chamber, each with four level switches. By flipping the switches, you can freely adjust and control the low-frequency, medium-frequency, high-frequency, and ultra-high frequency of your earphone.

KZ AS24 Review

The A24 housing uses new manufacturing technology. Different from general 3D printing, the new generation DLP 3D printing technology can realize high-precision printing of complicated internal structures of earphone cavities, with the advantages of higher printing efficiency, more uniform illumination, and higher curing strength. At the same time, the lot cavity model, designed and finalized based on a large number of users’ big data about the ear and ear canal, provides a comfortable wearing experience for listeners. It is made of a lightweight and skin-friendly resin material that remains comfortable to wear for long periods.

What’s in the box


  • Frequency: 20Hz-40kHz
  • Sensitivity: Standard Version: 112±3dB, Tunable Version: 109±5dB
  • Impedance: Standard Version: 112±3dB, Tunable Version: 109±5dB
  • Plug Type: 3.5mm
  • Pin Type: 0.78mm
  • Cable Type: Silver-Plated Cable
  • Cable Length: 120±5CM
  • Price: $100, $114 for tuning version.

I would like to thank KZ Audio for providing me with the review sample of  KZ AS24.


KZ AS24 Review

Looking at this picture you can an idea of how the switches affect the overall sound.

KZ AS24 Review

When I measured the AS24 in all switches up mode there is a bump between 1k-1.5K which cant be seen on official measurements. It’s probably because of my cheap coupler.

KZ AS24 Unboxing - FR Graph

My review will be based on all switches off – standard mode. I am a fan of the standard tuning of the AS24, so I have kept the switches down at almost all times.

KZ D-Fi vs KZ AS24

Like I said in my KZ D-Fi review this tuning suits my taste most. Polite lows with clear mids plus enough extension on the treble. Closest to natural tuning with a balanced sound signature. See the similarity? Some would say looking at this graph comparison that both IEMs might sound the same. But D-Fi has a single DD in it and AS24 12 pieces of BA drivers, they sound nowhere the same. Or should I put it like this? Does the AS24 sound 3 times better than the D-Fi? Yes, it does! Let’s dive in.


Bass has a good body and great resolution. For an all-BA design, the AS24 reaches remarkably deep and has superb low-end texture. It’s a rounder bass, that sounds organic. It isn’t an overly tight bass, but it has a good impact and certainly great dynamics. There is nice dynamic-esque air in the lows. The AS24 has a nice meaty and organic-sounding bass, that is hard to find in typical BA monitors. Sub-bass has a good foundation but might be missing some rumble. The upper and mid-bass are rich and have a great body.

It was only after more extended listening across different genres that I began to truly appreciate the quality and implementation of bass response. These IEMs helped me realize how many inferior sets blur detail in the bass, choosing instead to focus on superficially impressive punch. Some models generate visceral, almost uncomfortable levels of bass. Not an issue here. Bass on the AS24 is all about refinement and detail retrieval. The bass was pitched perfectly and revealed a rich texture that stayed light and controlled.

KZ AS24 Review

The transition from bass to mids is very coherent. The upper bass does give lower mids a slight boost and color them to a certain degree. Don’t expect an overly warm presentation though, that’s not the case. It’s rather a slightly warmed-up lower-mid segment. It shows a wonderful body and texture. Especially deep male vocals and low-pitched instruments get the most out of it here. They sound full and corporeal, which makes me enjoy them a lot. I like a good meaty lower end, and the AS24 definitely delivers.


Mids are rich and organic, and instruments have high levels of realism. Vocals, both male and female, sound smooth and emotional. They have decent warmth in them. The entire midrange has a good body and weight. They are not too thin and not too thick and the note sizes are just excellent. The texture of the midrange is very good. Mids are overall on the smoother side and they aren’t particularly grainy or edgy.

Vocals were also very strong through these IEMs. With male vocals, like Johnny Cash on his Cash album, all the timbre and tremulous nature of his aging voice were beautifully revealed. And then with female vocals, Stronger Than Me by Amy Winehouse was electrifying. I couldn’t move throughout the whole track, such was the grip her voice had on me.

KZ AS24 Review
You can see the BA drivers inside.


The top end of the AS24 continued the highly revealing theme all the way to the very top. What felt like a subtle lift in the highs enabled all kinds of details to come through, and I quickly forgot I was in critical listening mode and relaxed into the music. The tambourine on Jack-Ass by Beck was one standout. I could actually visualize the musician shaking and tapping it. Sounds obvious, but inferior sets just don’t tell the full story in the way these IEMs did, effortlessly.

AS24’s top segment has a clean and clear sound. It has good extension into the highest registers of treble. Some cymbal crashes and lower treble hits can become slightly forward. One thing I am happy to say though, is that the AS24 does not sound sibilant. I did not get any sharpness on critical tracks.

In the end, the brightness I perceived in the top end was in part because of the relative lightness at the low end. Almost as though the whole frequency response curve was tilted slightly up and to the right. The AS24 provides all the detail you could ask for.

KZ AS24 Review


The KZ AS24’s biggest strength to me is in its stage depth and layering. It manages to display all instruments very carefully by placing them with good distinction. As24’s soundstage might not spread the widest or tallest, but in-depth, it’s one of the best performers so far. The new flagship has a great sense of space and separates instruments very well. The background is quite dark, but not pitch black. With that in mind, it could do better in terms of contrast between instruments and background.

About the switches

Enabling the bass switches gives you an elevated sub-bass and upper bass, it does reach more into the lower mids. Makes the lower segment sound more forward and fuller. For my personal taste, this was too much bass, so I have left them in the downward position pretty much at all times.

The mid-switches add a few decibels to the mid-and upper midrange. Male and especially female vocals sound more forward-positioned. Musicians appear more in the front row and the sound is a touch more holographic. If you like to power up your vocals, these are the switches for you to flick.

Flipping the treble switches up gives you more upper-treble energy and prominence. Hi-Hat hits and cymbal crashes sound sharper, faster, and harsher. There is also more air perceived in the sound with these switches up.

KZ AS24 Review
Not the stock cable but the cable that the AS24 deserves.


The AS24 is KZ’s best-sounding IEM. Not because it has 12BA per side, but because it’s a very good engineering sample of a multi-BA earphone. Does it sound good enough for the asking price? Trust me, if this was another brand’s model the price tag would be 3 times higher.

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