KZ ZSX Review - Another One?


Another day another earphone release from Knowledge Zenith. Today we have a review of the KZ ZSX Terminator the latest model to come out from the Chinese budget IEM manufacturer. The ZSX comes in at well under $100 and is a Hybrid Earphone with six drivers per side for a total of 12.

Packaging and Accessories


The packaging and accessories right across the KZ range is straightforward and to the point. The company, no doubt, does this due to reduced costs through the standardization. The box and other extras across their lineup are similar if not the same.

The box is a simple small black unit with a foldable book like top. The foam insert protects the earphones, and the accessories are placed beneath. Its nothing fancy, there’s no crazy graphics but it is more than sufficient to ensure the earphones survive transit.


The accessories themselves are pretty limited. You get a warranty card, an instruction manual, four pretty average quality silicone ear tips, and one of the worst cables available from any of the Chinese manufacturers.

The poor quality of the cable is something that is now becoming inexcusable. Many other Chinese IEM companies at this price or below offer far better cables. This one is a copper-colored fragile braided affair. It is very prone to tangles and shape memory.

The other thing I can’t stand about KZ earphones is that bulging two pin connector. Its the only company I can think of that does this and quite frankly it makes using aftermarket cables a problem. This is because they do not sit over the connectors like the original. The correct way to implement a two-pin connector is with the port recessed into the housing. It is not protruding.

In any case, I would switch out the cable for an aftermarket model right away as this will significantly improve the overall feel of the KZ ZSX.

Build Quality and Styling


Excuse me if I sound fatigued but given the similarities across the KZ lineup its hard to get excited about their earphones. So many of them, as well as sub-brands like Triptowin and CCA look pretty much the same. Barr a few minor tweaks its all the same stuff. It’s an acrylic resin body on the housing and metal tips and a metal faceplate. The faceplate design varies across the lineup ever so slightly. The AS10 Pro is by far the nicest, but the ZSX is not a bad looking unit. It has a teardrop design with a slight overhang from the plastic housing at the bottom end. There is no shouty branding which I like, and it merely says 12 Hybrid in a tiny font.

Of course, the shell is translucent so you can see all the multi-driver goodness going on inside the earpieces. From the looks of things, they did an excellent job shoehorning all that tech into place.

In terms of build quality, they are good. An all-metal body would inspire a bit more confidence and resistance to drops and crushing forces, but truth be told these are well put together. The KSX feels sturdy in hand, and despite not going all metal the decision to reinforce the faceplate and the tips should ensure greater longevity on the IEMs.

Comfort and Isolation


I have absolutely no complaints about the comfort of the KZ ZSX. They have a very nice ergonomic design that goes well with my ear shape. I was able to wear them for hours on end throughout this review with zero discomforts. The housing is on the larger side, but that’s a given due to the internal design necessitating such size. People with smaller ears may be better suited to smaller earphones, but my reasonably average ears got on well in terms of comfort.

The KZ ZSX have a medium insertion depth. Combined with the large and dense body, they do an excellent job at blocking out noise when you use a good set of tips. In my case, I opted to use the Final Audio Eseries tips as well as some Spinfits. These insured a tighter seal and therefore less ingress of environmental noise, and it also had the side effect of increasing the bass just a touch.

Sound Quality


The sources that I used for the sound quality portion of this review will definitely be overkill for people buying such earphones. It was done so to evaluate them just as I would a more premium set of IEM’s. The good news is that when coming back to more budget-friendly gear, the KZ ZSX were just as easily driven. Hybrids can sometimes be picky with their power source, but you shouldn’t have any problem driving these directly from your phone if you so choose.

The earphones sound very good for the price. The sound is detailed and full with excellent musicality and subtle sparkle in the top end that adds energy to the presentation. Bass is done very well, especially about how it plays off the mids and treble to sound impactful yet not overbearing.


The Highs - The top notes of the KZ ZSX have a suitable extension and display a lot of speed and clarity. This was observed in two main ways. In jazz tracks observation, high hat splash sounds bright and crisp.’ It’s not in the sibilant territory, but it is on the brighter side of things, and that’s how I like it. For some people, this will take a few hours of brain burn to become accustomed to if your regular earphones have a rolled-off top end. Where I think the treble shines was in trance and EDM tracks where the tunes peak out in the top notes before the bass notes kick in. This makes them high energy and engaging in this genre.

The mids - If there is a weak point of the sound its in the midrange. It’s smooth and detailed enough. There is some warmth, but it lacks the full body and clarity of more expensive earphones. Still, we have to consider the price. In reality, the midrange isn’t bad; it’s just that the bass and treble are punching above their weight in terms of performance. I felt female vocals were best with the KZ ZSX possibly due to them sitting in the upper range of the frequency band. In the tower range of male vocals, they just sounded average.

The lows for me would have been the highlight if it wasn’t for the treble. I’m not saying one of these frequency bands is better than the other, but they complement each other very well. The bass is punchy and controlled, and it has perfect extension yet it doesn’t fall when many cheap earbuds are exposed. It doesn’t become flabby or overly exerted. It feels like KZ decided to hold off a little from their earlier bass-heavy tuning. They are keeping the ZSX it with enough sub-bass to please a mild basshead but not so much as to drown out the other frequencies and p*** of the purists.

The soundstage is average for an in-ear. There is slightly more depth than width, but it never sounds like its an out the head experience as you would expect.

Detail retrieval is far beyond what I would expect for an earphone at this price, but ’that’s only in the upper and lower frequencies. In the midrange, detail retrieval is more regular and in line with what I have come to expect from other similarly priced IEM’s


The KZ ZSX performed admirably in this review mainly due to the very good sound quality that has it punching a bit above its weight. They are a great sounding set of earphones and indeed one of the best I have tested at this price.

However, KZ needs to include better tips and cables with their headsets and get rid of that god awful protruding two-pin connector. The build quality is decent, and comfort was also good.

The good news is that if you drop a few extra bucks on an aftermarket cable and tips, you have yourself a well-rounded set of earphones that provide a detailed and engaging listen. Rating: Recommended.

The KZ ZSX are now available to buy worldwide from and other vendors.