The Ultra Cheap IEM Thread

Nice review, and at this price, they may be this year’s stocking stuffer. I’ve given away a few KZ ZSN’s from a couple of years ago. Would you say that these would be a distinct improvement? There’s always a few kids/tweens on my list. Koss Porta-Pros were a big hit.


Excellent review as always @Nimweth. I aren’t a great fan of the aesthetics but as @pennstac mentioned these could indeed be great stocking fillers.

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I have not heard the ZSN, but I have had the ZSN Pro, I didn’t really like it. I found it to be typical KZ V shape with bright upper mids/lower treble. The Emerald is much better balanced in my view and shows the general improvement in tuning we are getting now.


I had (or still have somewhere) the ZSN, the ZSN Pro and the ZSN Pro X. In my opinion, the ZSN was the best of them, however, the improvement in budget IEMs since then has been quite noticeable (although not in all models, some releases are still very bad :smiley: )

I actually have the CCZ Emerald and Melody incoming, so I have only really glanced at @Nimweth 's review, as I try to not read reviews of something I plan on reviewing.


On Amazon, it appears that Yinyoo markets both the KZ and the CCZ lines. As I’m a prime customer, I prefer to order from Amazon, the difference is negligible. These sound good enough from your review @Nimweth, that I’m ordering a few for future stocking stuffers.


Here’s an old review I wrote a few months ago but haven’t gotten around to posting. Finally have a bit of time to clear through my backlog. Thanks Hidizs for this providing this unit.

Hidizs Mermaid MS2 Review: Vocals Galore

Review written by @Fc-Construct

Review unit provided by Hidizs



As far as ChiFi goes, Hidizs is a brand that some may have heard of in passing but not haven’t paid much attention to. They’re mostly known for their affordable DAPs and portable amp/DACs though they have started to branch out into making IEMs. For today’s review, I’ll be looking at one of those IEMs, the Hidizs Mermaid MS2. Priced at $90, it’s a hybrid IEM with a 10.2 mm DD and a single Knowles BA setup. To be honest, I’m always a little apprehensive about reviewing gear at this price range considering how hyper competitive it is. Hopefully the MS2 will be able to stand its ground.

What’s in the Box?

The unboxing experience is pretty nice. Open the box and the IEMs are seated right on top. Below is a black box with a brushed aluminum top showcasing the Hidizs logo. Inside contains the 6 pairs of generic silicon tips and the 2-pin cable. The case has a magnetic lid and a rubberized inlay. I really like the stock 2-pin cable. It’s looks good, is well built, light, and supple with no cable memory. There is a little cable noise, however.

The IEM shell has a 2-layer faceplate where the outer part has the Hidizs logo that casts 3D-like shadow on the opalescent inner part. Unfortunately, it looks a lot better than it feels. The lightweight plastic used for the shell doesn’t evoke a sense of luxury. Still, it plenty comfortable for me and for the price that’s about all I ask for.



Generally, whenever I get a new IEM in the budget class from a manufacturer without prior history of excellence, I expect the worst. For the MS2, I thought it was going to be an ugly, bassy mess. I was wrong. The MS2 is a very vocal forward IEM with a bright signature. On the technical front, it’s nothing outstanding but solid. I’ll admit I was lukewarm on it at first listen but as I spent more time with it writing this review, I’ve come to enjoy it. The MS2 works particularly well for genres like rock and metal where its upper mids clarity works overtime.

Frequency response of the Hidizs Mermaid MS2. Measurement taken with an IEC-711 clone microphone. Comparisons can only be made to other measurements taken by this specific microphone. The peak at about 8-9 kHz is an artifact of the microphone. It likely does not actually exist as depicted here.


The bass of the MS2 is elevated enough to carry the beat of songs but isn’t the main star of the show. For the overall tuning, I think there’s a good balance of bass quantity. As for downsides, it doesn’t have a ton of depth and rumble to give low end oomph. Though it’s punchy, it’s dry and a little soft. Subbass notes sound rounded out without a strong sense of impact. Where the bass meets the lower mids, it starts to sound smeared and drum notes aren’t well distinguished there. On the upside, the MS2’s bass has a sort of lightweight quality to it. It’s pretty fast and doesn’t muddy up the MS2 too much. Bass guitar lines are coherent and well defined. Drums notes are a quick touch and don’t linger needlessly. For that reason, the bass of the MS2 particularly excels in (alt) rock, metal, and punk, those sorts of genres. I find that if you turn up the volume past a certain threshold, the bass quality perceptually improves and gains a confident step to the presentation of the notes. Just be careful with the volume.


The upper mids are the real focus of the MS2. But it steals too much of the spotlight. It’s a very vocal forward IEM and depending on what you’re used to or what you can tolerate, the MS2 has a good chance of sounding shouty. Personally, even though I have a pretty high tolerance for lots of upper mids, I’d say the MS2 crosses the line of being too much, especially at first listen. I definitely need to watch the volume knob on the MS2 unlike a few other IEMs where I can turn up the volume quite a bit before being overwhelmed by vocal overload. The upper mids energy of the MS2 brings a ton of clarity particularly with the electric guitars, snare, and vocals. They cut cleanly right through the mix without a moment of hesitancy with a nice bite to them. Though you could argue that it borders on being strident, I wouldn’t call it harsh. There’s a hint of sharpness to its sound and sibilance on some tracks but not enough to cause discomfort. Of course, your mileage may vary depending on your sensitivities.

With this much upper mids, you’d think the MS2 would sound thin. It’s… not so bad. The lower mids have sufficient volume to dissuade this notion. In fact, I’d say the bass actually bleeds into the lower mids and causes smearing in that region as mentioned above. My guess is that it’s an incoherency issue at the crossover with the DD and the BA. A little unfortunate as it is a stain on the overall sound quality and enjoyment for me. Though the mids may potentially be too intense for some people, I think Hidizs has gotten more right here than wrong.



The treble of the MS2 is lively, crisp, and sparkly. However I think some of that BA timbre comes out here in the highs. The decay of notes sound brittle. Coming straight off the upper mids is plenty of energy in the lower treble that brings a crispness to the sound that makes notes pop. From there, the MS2 has a 6 – 7 kHz dip that isn’t totally “correct” but helps it from being too bright. This sort of dip isn’t uncommon; a less exaggerated version of it can be found on the DUNU SA6. The effect of the dip manifests as a sort of unevenness to timbre. For the cymbals, you get the initial attack but the subsequent ring out is overly softened. For some tracks, it helps the MS2 be forgiving as it masks bad recordings. In others, it manifests as a sort of incoherency. Past the dip is another burst of energy heading into the upper treble region. Here is where the MS2 gets its touch of sparkle. Unfortunately, it doesn’t extend too far with the upper treble so the air that I’d like to see accompany the sparkle is missing. With better and better tuned IEMs nowadays, I find that sometimes the treble is overly dampened in pursuit of having a safe, unoffensive treble. While that’s a fair strategy, I like my IEMs to have a bit of treble spice and the MS2 offers that.



The staging is OK on the MS2. Both soundstage width and imaging are about average. You’d think an IEM with so much upper mids would sound totally in your face but that’s not the case. Yes, the vocals are very much pressed forward but the other instruments aren’t painfully congested. Like many IEMs, there isn’t much stage depth or layering. It ends up sounding relatively flat and compressed to an extent.

On the resolution side, it’s about what I’d expect for the price. Notes are clear with a good sense of definition. However some may critique it as having “fake detail” due to the MS2’s abundance of upper mids and treble energy. While I don’t fully agree with that line of reasoning, I do think that the MS2’s presentation feels superficial. When listening to a few of my other reference IEMs, they have a better sense of nuance and refinement, a subtle depth to the sound that adds greater enjoyment. The MS2 is a genre specialist as its lightweighted bass and upper mids clarity lends itself well to fast paced and busy tracks. My alt-rock tracks sound great while modern pop and hip-hop songs are rather middling.

Should You Buy It?

Possibly. The MS2 wouldn’t be the first IEM I jump to as a recommendation, but you know what, if you primarily listen to rock and metal tracks and can stomach a ton of vocals, the MS2 is not a bad choice at all. Those songs are comparatively elevated on this IEM. Admittedly, the price of the MS2 makes it a tricky proposition when other well-regarded IEMs like the Tin HiFi T4, MoonDrop Starfield, and Etymotic ER2 are right around the corner. Still, I do think that it does enough to differentiate itself on the tuning front to warrant a moment of consideration even if it isn’t the front runner of the budget IEM landscape. If you know what you’re getting into with the Hidizs Mermaid MS2 (which you should after this review), I think you’ll be reasonably happy with the outcome.


Sounds like a good alternative to FiiO FH3.


As always, this is also available in Spanish on my blog and on YouTube, links at the end of the post.


It has been a while since I tried any of the latest offerings from KZ and I somehow stumbled across the ZEX when it was announced for preorder. As it was a new combination of drivers from the brand and was at a very reasonable price, I placed the preorder and actually forgot about it.

It sat in an unopened box for a while until I saw somebody mention it on a forum and decided to check if I had actually received it or not (I had quite a few unopened boxes laying around). It was indeed there and I decided to give it a quick listen, I must say I was surprised at the first listen, so I put it on the burn-in rig and gave it the usual time before grabbing it again this week to test more.


Not much has changed in the KZ presentation, in fact, I don’t think anything has changed since the last time I opened a normal set of theirs. I mean, there have been a couple of “special” presentations, such as the ZAX, but this is just like any other of the many KZ offerings that have been across my desk.

A simple white box from which slides a tray with a clear plastic cover, showing the IEMs inside. Underneath this we get 3 pairs of silicone tips (including the ones installed), the cable and, well, that’s it.

Build and aesthetics…

While the shape of the ZEX is the same usual shape used by the brand, they are a little smaller than things like the ZSN range (only slightly), being the same size as the ZAX but with a bit more contouring going on. They actually look fairly decent for a set of IEMs that cost around 20€. I am not sure if the faceplate is plastic or metal but if I had to guess, I would say plastic. Overall I like the look of them, fairly discrete but without being too boring.

As far as the cable, well, here KZ have made a huge improvement in my opinion. Ok, it’s not a boutique cable with fancy braiding but it is miles ahead of the thin twisted cables that I was used to receiving from the brand. They haven’t even really done much to improve it, they have just covered a thin cable in a see through rubber coating, but it is enough for me to not want to throw the cable in the KZ pile upon opening the IEMs. My version has an inline mic and I am not sure if I ordered it like that on purpose or by mistake (or maybe that was the only one available for pre-order at the time) but it’s a shame as I wouldn’t mind having this cable mic free for when I use other KZ IEMs.


Let me start by getting straight to the point, the ZEX sound pretty darn good for a set of 20€ IEMs. There are more and more options in this price bracket lately, some of which are very decent IEMs that would make plenty of people happy, and I think that the ZEX should be put straight into the decent category without a doubt. They do have a few issues that I will comment on shortly but these IEMs are a set that are impressive upon first listen.

I say first listen because my first impressions were “wow, these have a lot of bass yet sound very clear!” As I have spent more time with them, there have been a few things that have stood out, making them still impressive but remind me that these are not perfect.

The sound signature is very much the typical KZ “V” shape found on the majority of their IEMs, with few exceptions. Over time, KZ has stuck with a similar tuning on most of their set and just achieved it in different ways, with different driver configurations, some working better than others.

In the case of the ZEX, KZ are using a single Dual Magnetic Dynamic Unit and what they call a Low Voltage Electrostatic Unit. An electrostat is not something found on many IEMs, even if it is not exactly an electrostat, and it does seem to work in favour of these specific IEMs.

I am going to get into the specific frequency ranges and usual steps in just a second but first let me make a note on tips. I have used the included tips (which I wasn’t overly keen on), foam tips (that made them a little dull), Final Audio Tips (which make them more impressive but show a bit of harshness that I am about to comment on) and also Xelastic tips (which fix the harshness but again dull down the clarity a little too much for me). So, my thoughts are based on using the Final Audio tips, tips that do enhance the bass and retain the clarity that I feel these are good at.

Starting with subbass, these have plenty of it. If you are looking for rumble in the low end, the ZEX deliver and manage to do so without losing control too much. As I have stated on many occasions, I am not one for elevated bass unless I am specifically in the mood, well, the ZEX are good candidates for when I am in the mood. “Chameleon” can not be said to be lacking anything at the lowest frequencies and while it is not the most controlled I have ever heard it, it is certainly good enough to be enjoyable. “Nara” is also a very good example of the fullness that the ZEX have all the way down to the lowest notes. Let’s just say that my hearing rolls off before the IEMs seem to.

In the mid and higher bass regions, the bass is still very present and is also clear and articulate. Listening to things like “Forgot About Dre”, where the bass line moves around between 50Hz and 100Hz, it stays present without anything seeming out of place. I listened to quite a bit of Hip Hop and EDM, enjoying the low end presentation of most of it. Moving to things that are less electronically focused, such as “Give Me One Reason” by Tracy Chapman, the bass is a little more elevated than I would choose but does a decent job of staying out of the way of the rest of the frequencies. With “Black Muse” by Prince, I did find that I wanted to dial it down a bit though but still listenable.

And I think that is where KZ have made a decent job of these IEMs. I don’t know where the crossover to the electrostat happens but the ZEX manage to keep mids and highs clear and present, even when the low end is boosted.

There is a dip in the mids as I mentioned, but the dip is not overly done, or at least the climb up at the end of the mids is enough to make sure vocals and mid centric instruments are present. I was actually very surprised at how detailed and clear these can be in the higher end of the mids and lower treble frequencies. Even for my typical vocal and acoustic instrument focused tracks, they do a good job of keeping everything clear and well presented.

The negative side, there is always a negative side, is that sometimes vocals and other parts of the higher mids can come across as harsh. They are actually not sibilant, at least they don’t add sibilance, but certain parts can be a little brutal at times. This is not all the time, just on occasions, but that can actually be worse at times, as EQ (or tip changes) to remove these harsh appearances seem to dull down the overall signature in general, becoming a little too blunt for my tastes.

Don’t get me wrong, I still feel that these are excellent value for their price, and would still be good value at a much higher price, but those peaks do take the enjoyment away now and again.

As far as soundstage, well, we are back in the average camp here. They are not bad but are nothing worth noting in this regard. Image placement is also acceptable, maybe a little over average, but again nothing out of this world.


I think the last set of KZ IEMs I reviewed were the ZAX, a more classic hybrid set up from KZ, and I must say that these are more impressive than the ZAX. By this I don’t mean they are better, I mean that they are more impressive in what they can do. I think that I can dial the ZAX more towards my tastes with my usual selection of music (not just the stuff on my test list) but they are not IEMs that I usually reach for, I have others that I prefer much more.

However, the ZEX are sort of a “Here, take that!” set of IEMs. I was literally surprised when I first heard them and I still am when I pick them up after listening to other stuff, especially with hip hop and EDM.

I would not put them at the top of my recommended list for my personal tastes but I certainly think they are worth (more than) their price. I would have no problem recommending them to people who want to party inside their head. They sort of remind me of some car systems that people spend a lot of time (and money) perfecting to get that Saturday night parking lot EDM party set up, and these only cost 20€.