Kz ASX wired earbuds review: High-end Chi-fi
The Kz ASX are high-end earbuds with detachable cables. They're among Kz's more expensive earbuds. They look like little gems, but do they sound as good as they look? Even when you remove the cables and connect the wireless adapter to turn them into Bluetooth earbuds? We find out for you in this review.
In this article
Pros and cons
Here are the pros and cons of the Kz ASX earbuds, so you can quickly see whether they're right for you.
| Pros | Cons |
| ✔️Perfect sound ✔️Detachable cables ✔️Optional wireless connection |
❌Larger earbuds |
Kz ASX specifications
- Price: €90
- Bluetooth: optional
- Frequency range: 10-40000Hz
- Resistance: 20Ω
- Sensitivity: 106dB
- Connectors: 3.5mm
- Range: 10m
- Cable: Audio (or wireless)
Kz ASX sound
The first time you put the ASX in your ears, it feels like walking into a concert just as your favorite band plays the first note. It's surprising and a joy to listen to. Beyond crystal-clear sound, these earbuds seem to recreate the distance between you and the source of each sound.
It's something to enjoy and experience. We're genuinely surprised by the sound quality, and honestly, we've never heard anything like it before. Yes, you read that right. This is the best sound we've tested so far.
Sound quality score: 9.5
Of course, these are wired earbuds. That means none of the budget had to go toward wireless technology, which is very expensive. In other words, everything Kz didn't have to invest in Bluetooth could go toward sound quality. That gives them a head start.
Now, about the sound. The biggest problem with many earbuds isn't that the bass, treble, and mids all lack quality. It's often that 1 of the three falls too far behind. In other words, we'd rather have bass, mids, and treble that all score a 6 than a 9, another 9, and a 3. With many earbuds, for example, the treble lets down otherwise good mids and bass.
With the ASX earbuds, every part of the range scores consistently high. Let's start with the treble. It comes through beautifully. In songs with a guitar, you can hear the click of each plucked string. The bass comes through beautifully too. It blends into the musical ensemble, to give this review a touch of sophistication. The mids can make or break earbuds. We've often heard good treble and bass let down by the mids. That's certainly not the case with the Kz ASX. The mids round out these earbuds and deliver a full sound unlike anything we've experienced before.
Microphone: how are calls on the Kz ASX?
Microphone score: 8
As you can see in the image above, the Kz ASX microphone is 'on fire'. The microphone simply sounds good. Hear it for yourself in the clip we recorded for you below:
Note: the microphone is optional
You can tell Kz is a true ChiFi brand, meaning Chinese HiFi. Their focus is firmly on sound, not the microphone. But if you want to use these earbuds with your laptop or phone (what else would you use?), it's a bit awkward if you get called into an online meeting or receive a good old-fashioned phone call and can't talk back.
That's why we only test and sell Kz versions with a microphone. Much more practical.
And the microphone is good! Not quite as exceptional as the Kz ASX's sound, but it comes pretty close.
Curious about wireless earbuds with the best microphone? We've put together a comparison with all the audio clips.
Fit: how do the Kz ASX feel?
Kz earbuds always come with silicone ear tips. They're in-ear earbuds, which means the ear tips go into your ear canal.
But the choice of ear tips here is unusual. Unlike those on other Kz earbuds, these are paper-thin. They flex nicely to follow the shape of your ear, but in this case, they flex too much.
Fit: 5 (included ear tips)
You can feel the metal housing that the sound passes through beneath the ear tips. That gets uncomfortable. We fitted our own foam ear tips to them. Since then, they've fit perfectly.
Fit: 7 (foam ear tips)
The odd thing is that other Kz earbuds don't need foam ear tips. They come with perfectly good ear tips, even in different shapes.
More power makes the ASX larger than its siblings
It makes sense that the sound chamber and housing need to be bigger to produce the Kz ASX's sound. All the components are slightly larger to deliver this level of sound quality.
So Kz had to find a smart way to arrange everything inside the earbud. Put any cheaper model next to the ASX and you'll see that the ASX earbuds are slightly bigger. But it's also clear that Kz has managed to keep the size in check.
Compared with the ZSN pro, for example, the ASX's sound quality is at least 2 times as good. Yet the earbud is perhaps only 10% larger than its smaller sibling. In that respect, Kz has done an impressive job of keeping the earbud reasonably small.
The Kz ASX fit well! You can wear them for long stretches, especially with foam ear tips.
Earbud controls
There isn't much to say about the controls, because they're very limited. These are wired earbuds, and the cable has a small control panel with a single button.
Controls: 6
You can use that button to pause or play your music. You can also answer the phone when someone calls.
Go wireless with the Kz Bluetooth upgrade
The Kz HD Bluetooth Upgrade Cable lets you turn these earbuds into wireless earbuds. Simply click the Bluetooth band into the earbuds where you'd normally attach the cable. Then you can easily connect them to your phone or laptop. You get both the great sound of these Kz earbuds and the freedom of wireless earbuds. A worthwhile upgrade.
The good news is that these earbuds work really well with the HQ Bluetooth upgrade cable. With other earbuds, we heard a slight hiss during use, but not here. The sound is clear and clean! We definitely recommend adding this cable to your earbuds.
Conclusion: are the Kz ASX good?
| Score | |
| Sound | 9 |
| Microphone | 8 |
| Fit | 7 |
| Controls | 6 |
The Kz ASX sound incredible. They're unmatched. In other words, we've never heard this level of quality in an earbud before. Beautiful bass, supported by the mids.
Alternatives
Which earbuds would you like us to compare these with? Let us know and we'll put them head to head.Others also viewed:
- Browse all our wireless earbuds articles
- These are the best earbuds under €50
- These are the earbuds with the best microphone
- Explore our in-depth article on QCY earbuds
- Also explore our article on alternatives to AirPods
- See the top 3 earbuds for running
- Also check out our hands-on with the Eardopes B6 pro.
