KZ ZEX Review: Rich Chocolatey Goodness in an IEM

Pros: Rich and Full Vocals, Fun and Playful, Excellently built and finished, Great Value

Cons: Detail, Bass Bloat, Slight unnaturalness in midrange tonality

Driver Setup: 1 Dynamic + 1 Electrostatic Driver

Price: US$22


Disclaimer: This review set was graciously lent to me by a friend and the review is written of my own accord. Should you find yourself interested in a pair, you can find it online here.

ANOTHER KZ in the house! This time, things are a little more exciting with a brand new driver set up. The KZ ZEX is a budget IEM at $22 packing a hybrid of a low-voltage electrostatic driver and a dynamic driver within. This is the first electrostatic driver implementation at this price point (together with the sister brand CCA NRA). I can’t wait to see what they have done with this pair.

Build Quality (Score: 9/10)

The build quality of these buds was honestly very impressive. These felt NOTHING like 20 dollar earphones. The shells have a very hard almost glass-like resin, giving it a good amount of heft to them. They also seem a little brittle and might shatter if you drop them from a height (please don’t try it). This is a good upgrade from the cheaper plastic shell we are more used to on IEMs like the ZX10 Pro, and EDX, among many others.

The faceplate is a matte aluminium material and the whole aesthetic just flows. Absolutely stunning product design. The ZEX also sports the new KZ cable, which is much more durable and less prone to tangling than the previous ones. These look and feel great and I’m really loving this new direction and approach KZ has taken. The one downside to the cable is that it is a little springy and doesn’t coil up as well.

Fit (Score: 8/10)

The fit is quite comfortable despite the buds being on the heavier side. It is compensated with a slightly longer than the normal nozzle to ensure a deeper fit and a good seal. I didn’t experience any issues with the buds threatening to fall out of my ears so good job with the weight distribution. The cable has a stiff ear hook but it didn’t affect the comfort.

Sound (Score: 6.9/10)

Frequency Response Graph of the KZ ZEX


  • Lotoo Paw S1
  • SMSL M200/Schiit Magnius

Music listened to

  • Chicago Symphony Orchestra – Beethoven Symphony 7
  • Boston Symphony Orchestra – The Nutcracker Suite
  • The Vamps – Cherry Blossom
  • Paul Kim
  • McFly
  • Vivaldi’s Bassoon Concertos
  • Greenday
  • Joscho Stephan
  • Family Company
  • etc


The bass notes are weighty and extend quite deep with a satisfying rumble and punch. However, the decay is a little slow and come across as a little muddy, especially evident in drumsets and tracks with fast-moving articulated basslines like a double bass. The bass is boosted and authoritative, pretty much in line with the KZ house sound. Instruments like bass guitars have a weighty and sub-bass element that supports the music well without overdoing or overpowering. It will certainly scratch that itch for a full lower end. That said, there is quite a bit of midbass bloating and can come across as a little too muddy at times, but nothing too terrible at this price range.


Mids are quite an interesting experience. The melody lines are quite rich and warm, with vocals quite bodied and well supported. In fact, the vocals are really tastefully presented and I especially enjoyed male vocals which were lush and rich. I honestly didn’t expect myself to enjoy these so much. This is quite unusual from the usual deep recession in the mids that KZ IEMs typically have. The ZEX has got to be one of the more balanced sets. KZ IS BALANCED? haha not exactly but relatively yes.

However, I find the music occasionally a little too coloured for my tastes. The tonality in the midrange is slightly off, and is apparent on certain genres, making them sound a little weird and warped. This is especially on songs that I’m familiar with and would pick up these issues really easily. Despite my best efforts to ignore it and let the “brain burn-in” do its job, I still found the sound a little too off. It doesn’t always sound bad, but it’s certainly how it’s meant to be. (or how I’d like/expect it to sound at the least).


Treble is rolled off and very subdued. This brings about a very dark sound, further adding to the colour of the sound. On certain tracks, this makes the sound a little too skewed and a little satiating. I would’ve loved more representation here actually, not even considering the sparkle or shimmer that you guys always wanna hear. Cymbals and high hats just fall flat and seemingly have their characteristics stripped from them. One positive thing I’d give it is that these don’t have terrible metallic or peaky like tonality to keep the tuning relaxed and pleasant.


The biggest flaw of the ZEX is the midrange tonality issue and accuracy. Of course, in terms of detail retrieval, there is much room for improvement, but considering the price point, expectations have to be managed and I’d say it’s passable.


Keep a lookout for this space. I am currently comparing it with the KZ EDX Pro, review coming up!


The ZEX really has a lot of potential. For 20 dollars, this IEM exudes quality in its build and features one of the best budget IEM stock cables I’ve seen. And to top it off the ZEX doesn’t sound bad. While there is much room for improvement in the tuning, KZ certainly proved that they are onto something with the ZEX. I very much prefer this to some of the metallic timbres that some of their BA hybrids have. Now perhaps that can work towards a slightly more accurate tonality and I’m sure they would have a hit in their hands.

This is got to be one of the best thought out and constructed budget IEM KZ has put out in a while. No harm going out to grab one of these, they won’t be replacing or toppling any higher priced IEMs, but I found these really enjoyable, which I’d say speaks volumes for itself.

Overall Grade: B-


Click HERE for our grading list for earphones

1 thought on “KZ ZEX Review: Rich Chocolatey Goodness in an IEM”

  1. Pingback: KZ EDX Pro Earphone Review - Perrivan Audio

Leave a Comment

Your email address will not be published. Required fields are marked *