Hey there fam. In today’s review, we’re looking at the KZ ZSN Pro, a hybrid IEM with one balanced armature driver and one dynamic driver. When I reviewed the original ZSN, it impressed me enough that I added it to my best universal IEM’s list.

It had a fantastic build quality, using a metal faceplate and transparent resin body. It was very comfortable to wear and had a decent but very tangle-prone cable. And of course, it had a really fun and engaging sound, which, when added to everything else made it ridiculously good value overall.

So, now KZ (Knowledge Zenith) has released this Pro version. So what has changed from the original? Well, here’s what I know so far. The faceplate has changed (slightly) and the dynamic driver has been upgraded to a dual magnet unit to improve control and frequency response and sensitivity. Apart from that, I’m not aware of any other changes so I guess it’s time to jump in and take a closer look.

Linsoul website: https://www.linsoul.com/

This sample was provided for the purpose of an honest review. All observations and opinions here are my own based on my experience with the product.

Package and Accessories

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Just like the original ZSN, KZ has opted for a simple and small box for the ZSN Pro. The box is white in colour and has an illustration of the monitors on the front.

On the back of the box is a list of specifications and company information. Inside the box is the familiar black, moulded plastic tray with the earpieces on display just above the KZ logo. Below the plastic is, of course, the accessories. Here’s what you get:

• KZ ZSN earphone
• Detachable 0.75mm 2-pin cable
• 4 pairs of silicone Starline tips
• User guide/warranty

A lot of people love the KZ Starline eartips. I would like to love them but they’re built for tiny pixie ears and are unusable for me. Anyway, it’s a standard KZ package which any KZ owner should be familiar with by now.

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Build Quality and Design

The ZSN Pro model is available in 3 colours: purple, grey and blue. My sample unit is the purple variation and I must say I find it quite handsome. The housings are almost identical to the original except for a couple of minor changes.

For example, the metal faceplates look the same at a glance but look closer and you’ll notice that the zig-zag pattern is now raised rather than grooved. Additionally, there is now a single screw and vent whereas the original had 3. Furthermore, if you look at the specs you’ll see that the weight has increased slightly from 23g to 29 grams.

The upgraded double magnetic dynamic driver increases volume by 30%, along with improved frequency response and higher sensitivity. Overall, the build quality is outstanding considering how affordable these earphones are.

Comfort and Noise Isolation

Like the original ZSN and the CCA C10 which shares the same shell, the ZSN Pro is a very comfortable earphone (at least for me). If you’ve tried either of the other 2 you’ll know exactly what to expect in terms of fit.

Passive noise isolation is quite good. According to KZ marketing, the housings can block out up to 26dB of external noise. Accordingly, there’s minimal noise leak so this is an earphone you can take anywhere.

Cable

Once again KZ have supplied their famous brown-coloured cable. This one comes with pre-formed ear guides which I much prefer over memory wire. The same transparent slot-design 2-pin connectors are present again, in addition to the stupidly placed Y-split that regularly makes the cable a tangled mess.

A right-angled and rubberized 3.5 mm plug is the final component of the cable. All things considered, it is a reasonably high-quality cable but I personally switch it out for a third-party option as soon as possible.

Sound

Gear used for testing includes the FiiO M6 and iBasso DX120 as my portable sources. On the desktop, the FiiO K3 was fed FLAC files from my PC via USB. Generally speaking, the ZSN Pro does not require any extra amplification and will work with any source including smartphones.

The KZ ZSN Pro has the same general signature as the original i.e. a very powerful bass with a slightly recessed midrange and an upper midrange boost. However, the upgraded version has some slight sonic improvements; it’s not so much a different tuning but an alternative one.

Bass

Undoubtedly the focus and the star of the show, the ZSN Pro’s bass is big, bold and bangin’. The amount of gusto in the low end should satisfy anyone who likes a large lick of bass and even certified bassheads will probably get a kick out of this.

With the upgraded dynamic driver in place, the Pro has even more impact than before. Sub-bass notes hit you like a subwoofer with a physical, palpable character. This is not an IEM for the faint of heart where bass is concerned.

The mid-bass punches hard and has a relatively speedy response for something with this tonality. It maintains an admirable pace and even holds up to tracks like Thundercat’s “Uh Uh” without bogging down.

Mids

There’s a little bass bleed present, providing extra warmth and body to the lower mids. Deeper male vocals lose a little bite in the mix. This can be seen in songs like “Buildings” by Katatonia where the vocals feel blanketed by the earphones lower registers. Female vocals fare better and rise out of the din more clearly.

Treble

The Pro is fairly lively in the treble and it needs to be to counterbalance that powerful bass. Fortunately, it stays smooth enough to not be jarring although I feel the timbre of crash cymbals is a little off-kilter. Honestly, though, the fact that I’m even talking about timbre on a $20 earphone indicates that it’s still pretty darn good. While it won’t mask a recording’s inherent sibilance, it doesn’t add any and I find the tone mostly pleasing.

Soundstage

The soundstage is fairly intimate but it feels natural enough. There is more depth to the stage than there is width, creating an elliptical shape that stretches out in front of the listener. Instrument separation is good and imaging is moderate.

Comparisons

KZ ZSN

Naturally, people will be curious as to how the ZSN Pro measures up to the original model. The first thing I noticed is that the Pro sounds fuller and thicker. The new dynamic driver has better extension and thicker mid-bass notes. While it does feel more controlled, it’s as though KZ boosted it even more than on the original just to highlight the fact.

As we go into the midrange, the extra punch in the bass carries over to here making it more full-bodied and rounded. Male vocals are softer on the ZSN Pro but there are improvements in the upper midrange. The ZSN’s upper mids lacked body and the Pro sounds fuller and less grainy.

The ZSN Pro has a more forward lower treble from 4-7kHz while the ZSN peaked earlier at 3-4kHz. To my ears, the Pro’s lower treble is a bit more even and for the most part, handles sibilance better. However, the ZSN upper treble has a more natural timbre.

Conclusion

So is the KZ ZSN Pro a true upgrade from the original ZSN? In some ways it is but in others it’s not, making it more of a side-grade. Which one sounds best to you will probably just come down to a couple of key factors. At first, I was ready to throw my hat in the Pro’s corner but really both models have a lot of merits.

The difference between a hero and a coward is one step sideways.

Gene Hackman

I just wish that KZ had been able to implement the new bass driver without boosting the quantity of the bass, which was already borderline excessive in the first place. Apart from that though, we have to keep in mind that this is a $20 earphone and I’m willing to acquiesce on some minor quibbles. Assuming you like some phat bass, the KZ ZSN Pro is another KZ value overload.

Specifications

• Weight: 29g
• Interface: 0.75mm
• Frequency: 7-40000Hz
• Impedance: 24Ω
• Sensitivity: 112dB/mW