top of page
  • Writer's pictureinToit Reviews

KZ ZSX: an IEM that Terminates the Competition?

Updated: Jan 30, 2021

Hey guys, welcome back to the neighborhood. Let’s talk about the KZ ZSX. Let me go ahead and say up front, that I’ve been putting off the review of this IEM for way too long… And, I really wanted to do this IEM justice. For IEM’s under 50 bucks, this won’t be the top pick for everyone, but to me it’s a good one to consider.

So, let’s get InToit...

The KZ ZSX is the successor to the KZ ZS10 Pro, and it is aptly nicknamed the Terminator. Maybe the idea is that this IEM terminates all others in its price range? I don’t know about, but, like the terminator, it is somewhat intense in regards to its overall presentation, and also like the terminator, I love it!

It tends to push sonics towards your eardrums through-out most of the frequency response spectrum. On graphs it looks like there might be too much of a mid-recession, but I ultimately don’t perceive this to be the case, as it sounds more like other frequencies are elevated in their intensity rather than the mids being recessed. Vocals are well pronounced as well, but not overly forward. The treble and upper mid-range are also pronounced, but rarely harsh; although this set does test my treble tolerance at times. As its mid-range does not appear to drop below 10 DB from any of its peaks for the most part, I would classify this as U-shaped IEM rather than V-shaped one (I know I'm being a bit kind here).

The ZSX also has a sub-bass emphasis to it, and it rolls smoothly from the mid-bass into the mids. Impact is good, and it digs relatively deep; not as deep as say a TFZ No.3, but I think the bass magnitude will be enough to satisfy both bass-heads and audiophiles alike, without offending either. The bass seems to be relatively fast and punchy when it needs to be, and soft and somewhat looming when other tracks call for that. Mid-bass lovers might find the bass somewhat lacking emphasis in that region and upper bass registries, but I’d much prefer this presentation to one where the bass overwhelms and dominates the mids.

Because most sonics have some forwardness to them, I would say that the ZSX’s biggest weakness might be listening fatigue due to its overall intensity. This is a fabulous IEM to pull out and listen to every once in a while, but I don’t think I could listen to it on a daily basis without it increasing my overall level of anxiety. The fit is also a bit on the chunkier side, and while I ultimately found it comfortable for shorter listening sessions, it did wear on me after hours of use.

Another weakness of the ZSX is that it is relatively sensitive. It does tend to pick up hiss on amplifiers that are rather noisy; however, It does play well with the IE-Match from iFi if your amplifier of choice is too noisy for it. The Zen Dac from iFi was too noisy to run this unit balanced, but running the amplifier unbalanced surprisingly produced limited additional noise. My favorite dac amplifier combination for the ZSX, which I tested, was running the Gold Note DS-10 as the dac into the Geshelli Labs Archel Pro using the iFi IE-Match.

My favorite tips for this set included JVC Spiral Dots and Final Type E tips, both for sonics and comfort. RHA Dual Density Tips also lessened the intensity a bit. I will also note that the cable that came with the ZSX wasn’t the worst, and the included microphone has performed relatively well on discord chats. Some people have report sound degradation with the microphone cable, but I could not discern any difficulties with my set.

**Please note that since this review was published, I have learned that KZ Starline Tips do seem to be included in the box with the ZSX. So you get one set of medium, rounded silicones, and a full set of KZ Starline Tips in the box! This is big news as I ultimately came to prefer this set with KZ Starline Tips. Please note this in your purchase decision, and I apologize for missing this initially.- Your Friendly Neighborhood Reviewer

The sound-stage could also be considered somewhat of a weakness for the ZSX. Generally, I would describe the stage as rather average to intimate. Its not as intimate as say something like and Etymotic, but it isn’t particularly wide or deep either; however, it does have more depth to its stage than it does width. Irregardless of its limited sound-stage, sonics do image accurately within space, separate well, and are distinctively defined. In spite of its limited staging, I never really found it to get overly congested.

Despite its driver count; consisting of 5 individual balanced armatures, paired with an additional 10mm dynamic driver per channel, the sound was extremely integrated well overall. In fact, for a hybrid, this was one of the best integrated IEMs that I’ve ever heard, which was extremely surprising to me given its cheaper price-point.

The KSX was also extremely detailed to my ear, again this characteristic was especially surprising to me given its price-point. But with this clarity comes a certain double-edged sword- the ZSX is also very revealing, which means that it exposes poorly recorded music. If there is grain in the track, you will hear it, and I wouldn’t say that it produces sibilance in music, but I would say that if sibilance exists in the track itself, it isn’t going to really cover it up either.

Some have reported that the ZSX might have a metallic timbre to it due to its heavy use of balanced armatures, but I did not find this to be the case in my testing on my gear. Instead I found the ZSX to have a rather natural, neutral timbre, which was clear, intense, and invigorating with just enough air at the top end to elevate this IEM past most of its competition at this price-point.

In the end, the KZ ZSX is a revealing, detailed IEM for intensity junkies, that I can’t really recommend as a daily driver for most, but would recommend as a secondary IEM for people to get their clarity fix every once in a while. Its timbre was surprisingly accurate and overall presentation pleasing. I’d like to think that maybe KZ choose the minicar of a terminator because its hybrid design consisting of balanced armatures supported by a dynamic driver is kind of like a terminator with living tissue integrated on top of a metal skeleton.

Lastly, for those of you wondering, I’d definitely recommend the ZSX over the ZS10 pro overall, for most people, in most circumstances; but for those looking for a slightly more relaxed listen with more of a mid-bass than sub-bass emphasis, and a better fit than ZSX, you might want to stick with the ZS10 pro. The ZS10 pro may also fit the masses better due to their more ergonomic shape, but again, I had no difficulties with the fit of the ZSX.

InToit Reviews Twitter:

Join the InToit Reviews Discord Server:

689 views0 comments

Recent Posts

See All


Post: Blog2 Post
bottom of page