KZ ZS12 Pro X Review
Intro
Hello, today I am reviewing the latest KZ Audio hybrid iem named the KZ ZS12 Pro X. The ZS12 Pro X is another rehash of an older version that I was really looking forward to testing out. I want to thank Keephifi for sending out the KZ ZS12 Pro X in exchange for a full review and feature at Mobileaudiophile.com. Now, the ZS12 Pro X comes in with an MSRP of around $50 as it’s a six-driver hybrid iem consisting of one dynamic driver and five balanced armature drivers. On top of that KZ also added in four dip-switches which do switch up the sound giving many slight variations of the same tuning. So I was pretty excited to check this set out.
Ya know, KZ has really been doing some great things of late and many of sets over the course of the last couple years have all been very good against their relative price points. I’ve seen it firsthand as I’ve reviewed a number of them myself. Those sets include:
– AS16 Pro
– VXS
– CRA+
– PR1 Hifi
– EDCX
– Linglong
– ZVX TWS
– D-Fi
– Duo
– EDXS
– AS24
– Krila
– AZ20
– ZAT
– Rhapsody
– PR3
Incremental changes
Feel free to check out any of their past sets above. However, the point is that most of those sets grade very high against the field of iems and audio devices within their price ranges. Once again KZ listens to the consumer and makes incremental changes which ultimately wind-up being the next in each respective series. We’ve seen this occur countless times with too many sets to name. However, this is also how KZ/CCA keeps getting better and better. Many people dismiss this brand, and I wish they wouldn’t because KZ truly do a great job. The ZS12 series is another very solid one which trumps the ZS10 models or CCA’s version the C10 series. I am very curious to hear this set and will begin listening the second burn-in is complete. So, without further ado, the KZ ZS12 Pro X everyone….
Non-Affiliated Purchasing Link:
Disclaimer:
I received the KZ ZS12 Pro-X from Keephifi as a review sample and in exchange I will conduct a full review and feature at Mobileaudiophile.com. I have not received any payment or any other form of compensation for this review. This set is a review sample iem. KZ or Keephifi has not requested to pre-read any review and doesn’t have any control over “what” or “when” anything gets published to mobileaudiophile.com. All thoughts within this review are my own, though please take note that I will always have my own biases. This is impossible to get around. I try to be as objective as my subjective self can be, but this is an opinion piece folks. Thank you to Keephifi and thanks for reading.
ZS12 Pro X Pros
-Very solid build
-Dope look
-Price to performance
-Four dip-switches (con to some)
-Very dynamic and energetic sound
-Analytical lovers will like this set
-Deep and impactful bass that comes through clean for the price
-Midrange has nice presence, detailed, good energy, natural for a hybrid
-Crisp, punchy, and sparkly treble
-Nicely detailed, great resolution
-Instrument separation
-Soundstage is better than I would’ve thought
ZS12 Pro X Cons
-Same ole’ KZ iem shape
-Cable
-Note weight is on the thinner side
-Warm, rich, lovers may want to pass as this is more analytical
-Nothing else for this price
Gear used for testing
–Ifi Go Blu
–EPZ TP50
–Simgot Dew4x
–Aful SnowyNight
–Fiio Q15
–iBasso DX240 with Amp8 MK2
–Shanling M6 Ultra
Packaging / Accessories
Unboxing
The KZ ZS12 Pro X arrived at my home in a regular small KZ box. Nothing new there. Of course I didn’t expect to see something different. The same as most every KZ set you simply slide off the sleeve which uncovers a piece of plastic covering the earphones which are sitting in foam cut-outs. Underneath that layer you’ll see a few baggies. Inside of those baggies you’ll find the cable, eartips and well as a dip-switch tool. There really isn’t any more to it folks. Again, after so many KZ sets you really don’t expect a whole lot as it’s widely understood that KZ puts most of their effort into the earphones themselves rather than extras.
Eartips
So, the ZS12 Pro X comes equipped with four pairs of eartips in total. That is, one pair of large sized slow-rise foam tips and three pairs of KZ Starlines silicone tips. The Starlines come in S, M & L and have a narrow bore with a nicely firm flange, longer than usual tips. I will always enjoy receiving KZ Starlines as I do believe they are very handy tips to have on hand for many different situations. Basically, when you need them, they come in handy. Also, it’s always good to have some slightly longer but also more rigid tips. That said, I went back and forth with the Starlines and the KBear 07’s. I probably spent a hair more time with the 07’s but I do feel the Starlines fit the ZS12 Pro X very well sonically.
Cable
Another section that’ll go very quickly. The cable provided within the packaging of the KZ ZS12 Pro X is no different than the last 25 KZ sets that I’ve received (other than the CCA Hydro). To be exact it’s a white, almost opaque colored QDC style 2-pin SPC (silver-plated copper) cable that runs flat instead of in a braid or twist etc. and terminates with a 3.5 single ended 90-degree jack. I know we complain about these cables because for hobbyists, cables matter. However, it’s really not a bad cable and it does the job it was created to do and that’s to play music. So, if all you can afford is the ZS12 Pro X, and only the ZS12 Pro X, then please don’t worry, the included cable is more than capable of providing you with a great listening session. Of course, now that I’ve said that I should make note that I actually did swap cables for a 16 core Fedai SPC balanced cable. I listen almost primarily using my balanced sources and so it only makes sense for me.
Build / Design / Internals / Fit
Build Quality
Friends, if I’ve learned anything over the years about KZ, it’s that they almost always go above and beyond in the build quality. Of course, you do hear some folks complaining about glue and other things on some lesser expensive sets (like any brand). However, I am very impressed with the ZS12 Pro X. How could you not be? It’s made entirely by way of die-castings and also made entirely of a zinc alloy material. It’s beefy and dense in the hand, slightly weighty, obviously very durable and is coated with two layers of electroplating. Just a very nice build that I am very happy with. Now, the ZS12 Pro X does take on the exact size, shape and the exact mold of some of their other sets. They’ve actually used this die mold forever for their sets. Looking back, you can find many with the exact shape as this one. I don’t blame them either because it is a very ergonomic and reasonable build which should fit just about any ear. You’ll also notice on the faceplates is what appears to be a semi-open back style mesh. Now, I don’t believe that the ZS12 Pro X is actually semi-open back and I’m much quicker to say that it is all for aesthetics. Beyond that you do have a few small vents as well. Looking at the nozzle I’d say it’s about medium length and roughly a hair over 6 mm in width using my calipers. Beyond that, you’ll notice the dip-switches on the back side. Same switches as other KZ sets, but I’ll speak on that in a little bit. Also, there is a standard version without dip-switches. Obviously, my set is the tuning version. Anyways, the ZS12 Pro X is really a nicely built $50 iem folks.
Design
I really like the texture on the surface of the faceplates. It’s a very slight grittiness or roughness on an otherwise smooth shell. Couple that with an all-metal build, slight weight, and it just feels like a little tank. The KZ ZS12 Pro X is an all-black iem with a sweet looking design. You have the diamond plate pattern on the faceplates which is always a cool look. Of course, we’ve seen a few others (KZ/CCA sets) carry this pattern, or at least something resembling this pattern from KZ. The all-metal design with the black textured coating is a very tough look and feels great in hand.
Dip-switches
As I said, the KZ ZS12 Pro X comes in two variants which can be purchased at KZ-audio.com. Those two variants are called the standard version and the tunable version. It’s the tunable version which this section will be referring to as that is the version with four working dip-switches. Now, the way the switches work on the ZS12 Pro X goes like this: Turn the 1st switch “on” will increase the low-end by what KZ refers to as “1-level”. I assume 1 level is about 1-2 db’s. So, flip the 1st switch on and increase the bass by a couple db’s. Now, flip the 2nd switch on and it increases the low-end by two levels or 2-4 db’s. The 3rd switch follows the same pattern as the low-end will be increasing 3 levels. Now, the 4th switch flips the script and flipping it in will actually decrease the highs by one level, or 1-2 db’s. So, like all other KZ/CCA sets which have dip-switches, they make the ZS12 Pro X also very easy to understand and it’s very intuitive to use.
What’d I use?
Honestly, I really enjoy “all switches on” … for some of my listening anyways, and I liked switching it up drastically with the “all switches off” as well at times and my mood. Though the majority of the time it was all switches up. Truthfully, I like a few different switch settings and the ZS12 Pro X does provide different variants to the sound. However, for review purposes I went with the basic curve yet adding one level of bass to the low-end. Now, for review purposes I will use “1” to equal “on”, and “0” to equal “off”. Therefore, the first two switches flipped would look like “1100”. That said, my critical listening switch settings looked like this: “1111”. Sorry for the wordy confusion there. Lol. I like the balance of the 1st or second switch only on. It balances the dynamic peaks of the lower treble with the bass shelf. Please comment below if you need more understanding on this subject.
Internals
The ZS12 Pro X is a six-driver hybrid iem consisting of one dynamic driver and six balanced armature drivers. Once again KZ went with their very popular and fairly well regarded 10mm Super-Linear dynamic driver. This driver is responsible for the low-end as well as the entire midrange. KZ did this to keep coherence within the mix. Which makes sense. They also used a two 31736 balanced armature array (basically two BA’s in one) for the lower treble through the mid-treble and two 30019 balanced armature arrays for the highs. This seems like a solid way to tune this set, and I do think it paid off for KZ and I’ll explain that later in the “Sound Impressions” portion of this review.
Fit / Isolation
As far as fit is concerned, I have zero issues whatsoever getting a good seal with the ZS12 Pro X so long as I have tips which accommodate my ears. The ergonomics are similar to any set from KZ which has this build mold. For me it’s pretty good, maybe a little fidgeting trying to get it perfect, but no issue at all. Whether they’ll fit your ears is beyond me though. That I don’t know. I assume they should fit just about everyone perfectly fine. Isolation is about average to my ears.
Drivability / Pairings
Mobile Listening
The KZ ZS12 Pro X has an impedance of 25 ohms and a sensitivity of 106 db’s which makes it a very sensitive set of earphones. Well, I should day they are about the average for a set in this price range. Give or take a few db’s. Anyways, the ZS12 Pro X is very easy to drive from most any source. Even using my iPad, I had zero issues and even some headroom. Using KZ’s own KZ AZ20 Bluetooth adapters even worked like a charm and actually has great synergy with this set too. Just an FYI if you own the AZ20. At any rate, the ZS12 Pro X is driven easily and doesn’t scale abnormally well with more power. It scales to an extent and then you begin to see a plateau effect. Very similar to other sets in this regard. Obviously more power will slightly add a pinch more in dynamics, however, the sound is already tight, already very clean and so I just don’t feel I need a tone of power. I think pairing the ZS12 Pro X should be more of a priority.
What did I use?
So, I used many source devices during this review period. Fifteen in total. However, I used about 7 sources the majority of the time once I witted down the Pairings that I enjoyed the most. In the case of the ZS12 Pro X, it comes across as well. Balanced, neutral in tonal color and I honestly don’t have an exact source tonality preference that works across the board. Meaning, I used warmer sources like the Shanling M6 Ultra, and I used closer to neutral sources like the EPZ TP50, Aful SnowyNight or Fiio Q15. I feel the ZS12 Pro X is right in that sweet spot tonality-wise to work with many different source tonalities. Also, as I said I don’t hear a huge upgrade with a ton more power. Only to an extent. I think the real upgrade in sound as far as source devices are concerned more-so comes through more talented devices, better dac chips, better amping, cleaner devices, etc. This should be obvious, but this isn’t always the case.
What do you need?
I feel that you simply need a source device that you enjoy. Of course, the better the device, then it’ll equate to better sound. I may advise a decent dongle dac. More power does help to a degree and so getting a decent dongle dac should provide a better listening experience for you without breaking the bank.
Sound Impressions
Note: folks, I need to preface a few things prior to commenting on the sound of the ZS12 Pro X. The first thing would be that I did hear a nice difference with this set from pre-burn to post-burn. I know, I know, I’m full of it, it’s all in my head, Yada Yada. Friends, I noticed a definite difference in the texture that I hear coming from the midrange than prior to burning in this set. I gave it only about 24-30 hours in total. Nothing crazy. In fact, I have zero idea if it even needs that long for what I heard. It may be two hours. The point is that I certainly heard a difference there. Also, I listened using the “1111” and “1110” configurations for most of this critical listening session. That said, these impressions can be skewed one way or another by using the switches. So, I’m asking you to take that into consideration when reading. I use only flac or better files which are stored on my devices for listening. I rarely stream anything as I much prefer music on file. UAPP (USB Audio Player Pro) is my favorite player to use as I simply love the aesthetic. At times I’ll revert to Hiby Player and Poweramp too.
Condensed Sound Between the 20’s
I found the KZ ZS12 Pro X to be a nice dynamically-balanced sound. All truth…I wasn’t expecting this outcome folks. I was expecting something a bit more strident towards the top end. A bit brighter I suppose. However, I have been pleased with what KZ was able to do. I really am impressed by the sound performance of this set and where the ZS12 Pro X fits against other sets in its price point. Really a well-tuned iem folks which can battle it out against more expensive sets in my opinion. Of course, the sound signature does have to align with what you enjoy for that last comment to hold any water. For me I like the well-controlled energy on tap with this set. However, I am beyond impressed that KZ was able to tune this iem to have a very coherent replay. Sometimes you get sets that have that energy, but they also have micro distortions, timbre issues, speed issues or timing issues between drivers which makes them sound not as mellifluously comprehensive. Better said, the transition between bass, mids, and treble and between each driver used is not as fluent. Not with the ZS12 Pro X. No sir, KZ made sure to transition each driver very nicely with smooth transitions.
What’s it sound like?
I hear an almost W-shaped sound out of this set. Perhaps U-shaped, but I am much more apt to say W-shaped due to the slightly forward midrange. The tonal color is closer to neutral than anything else with a very crisp sound as well. The ZS12 Pro X actually has that great balancing act of coming across just as smooth as it is crunchy and crisp. I’d say it leans brighter towards the top end and though there is a low-end emphasis, it isn’t the type which warms the mix to any great degree. There’s solid energy on this set, but the way the drivers handle that energy is the impressive part.
Each 3rd of the mix
You have a very tight, well-textured, well-defined and very impactful low-end. It is dense enough in its body and compact in its fullness, but speedy enough in its note recovery. Low-end transients are quick with a hard edge to notes. Nothing pillowy here. The midrange is as clean as a whistle. Speckless, almost pristine with just a hint of coloration from the low-end. I hear fantastic details while also retaining some sense of musicality and emotion to my music. The midrange has a natural style timbre with just a pinch of bright energy. Really nice and clean. The treble range offers that good bite, good brilliance, nice and bouncy style cadence that also offers very nicely contoured notes. Well, generally. Of course, some tracks may make me a liar, but I found this to be the case most of the time.
Condensed Technicalities
Technically, the ZS12 Pro X is very well detailed as I miss almost nothing in my music. What I enjoy is that KZ didn’t sacrifice tonality to get those details. The timbre is still very nice, closer to natural than I ever would’ve thought. That all translates to a set with good control over the mix. Vibrant enough, dynamic enough yet micro-details are still brought to the forefront. Transients are fairly quick as far as I can tell. I hear good instrument separation and pretty good imaging. Layering is decent too for the price. I also like the soundstage in that it’s wide with a very open and airy feel to it. It isn’t entirely clogged with tonal characteristics as I do hear and sense some space. It’s actually a nice mix. In fact, for me the entire sound as a whole comes across pretty darn nice and for the $50 that KZ is asking for this is a great deal.
Bass Region
Friends I feel KZ did a nice job of presenting the low-end here. Using “1111” I found the bass to have decent definition, a nice impact, good extension and what I’d characterize as a natural fullness. The bass does not sound overly colored as the treble does a very good job balancing the overall sound. Honestly… It’s a nice sound for the price folks. Obviously, there are sets which hit harder, deeper, and with more authority, but the ZS12 Pro X does so with an above moderate thump and boom, yet without yucking and mucking up the midrange while also keeping a good texture to sub and mid-bass notes. Now, I’m sure that some folks may want a bit more oomph within the low-end and even I do at times, but by-and-large I was able to listen with a smile across my face. Maybe bass resolution could be a bit better I suppose but seriously, this set costs $50. I can tell you this, the bass does have decent density and can make its way around complicated tracks pretty well. I noticed that on heavier bass tracks that there is some loss of control, but I think that’s more of an after effect from the recording more than anything. In my opinion this is a well-represented bass region that can hit hard and get out of its own way very well.
Sub-bass
I have a hard time telling if the sub-bass carries more of an emphasis or if the mid-bass does as they seem to share the spotlight rather well. However, one thing I do know is that the ZS12 Pro X can reach deep levels of bass and get downright dirty when it needs to. It has a guttural ability to reach moderately deep pitches. Having said that, I don’t feel that this sub level energy persists or affects the whole of the spectrum. Not to a detriment anyways. I mean, it’s understandable that every area affects other areas of the mix to some degree, but the ZS12 Pro X really keeps tight reins on where it passes its influence on. Anyways, this is a cleaner sub-bass that has a more concrete note edge and with good note control. Listening to “Paradigm” by The Head and the Heart shows this dense depth pretty well. There’s a fullness there yet with a rather clean decay, not so reverberant that harmonics steal the show. It’s tight, nothing soft, lean yet dense mass but not overly emphasized. Or “Groove” by Ray Wylie Hubbard is a track which hits hard early and the ZS12 Pro X does it justice with a dirty rendition of this track. That’s “dirty” in a good way.
Mid-bass
The mid-bass also has that controlled and boomy attack that doesn’t congest the spectrum. It’s actually pretty darn tidy if you ask me. Very nice for a $50 iem. I like how the mid-bass represents this area with a good-sized emphasis, certainly it’s meaty and has some serious slam. Certainly not basshead levels but a good level for those who enjoy a decent amount of low-end heft. But just like the sub-bass I don’t hear it costing the midrange any resolution. I feel the mid-bass transitions into the mids in a healthy way. Maybe not the most pristine in definition due to the fact that it is slightly bigger and because it does carry a bulbous punch. But, for the size of this mid-bass it really does keep a cleaner punch than most sets in the price point. Listening to “Billie Jean” from Weezer I love the quick thunder of the kick drums which are recorded weighty and deep toned. The ZS12 Pro X there’s a nicely rendered attack with a robust and authoritative boom, but the nicest thing is that it has a hard lined note contour. It’s concise, compact, and never hazy. Just a nice slam which works for many different genres and tracks.
Downsides to the Bass Region
I think that if I were to outline some downsides the main dissatisfaction would be from bassheads who yearn for even more rumbly goodness, more meat and a heavier handed drone. I feel the KZ ZS12 Pro X does have some of that good weight, but it comes in the name of dynamic balance. Not willing to risk messing up the midrange clarity for some extra low-end db’s. I’m sure KZ was tempted to add even more thunder done low, but they held back and made sure to tune a relatively clean bass region which should satisfy anyone who is a fan of good bass. Also, let’s not forget that this is $50 bass. Please don’t think I’m comparing the ZS12 Pro X against $200 sets or anything. It’s good for what it is. Also, obviously there will be those flat bass lovers. If that’s you just keep on moving, you won’t like this set, even on the least bass switch setting. I honestly have no other complaints or slight infractions for this set from my point of view. Friends, hear enough iems to know when something is good and when it isn’t and the ZS12 Pro X… is good.
Midrange
The mids are the type which carry a leaner note profile. Well, warmer and slightly thicker at the low-end of the mids and brighter and more shimmery towards the top end of the midrange. I feel that the mids are not pushed back very far into the sound field. Meaning they aren’t too recessed for my liking. In fact, the midrange sounds a hair closer, but not to the point that they sound boxy, or too euphonic. They are simply nice for what they are. I hear a midrange that is generally smooth yet with brighter overtones. Not the warm-smooth type of sound that most people would think. However, this smooth note structure has plenty of crispness when needed. This comes from the more vivacious upper midrange & treble region trickling down to the heart of the midrange and finishing notes with that last little bit of sparkle. I also hear a neutral sound in this region as well. Just relatively clean and leaning more towards precision as well. Even analytical. Now, transients move quickly here. They come and go in a breath with glass lined note outlines and plenty of air in the sound. Nothing even remotely congested on this set. Much more refined than most other KZ sets in the price point. Micro-dynamics are picked up fairly well which help illuminate the subtle little micro-details all the while showing off good instrument separation. So, if I were to describe the mids to anyone (kinda like I’m doing now), I’d say that they are one part clinical/refined and another melodic/musical. Not as emotionally gripping but a nice and coherent sound in this region.
Macro-dynamics
The midrange also shows off some pretty vivid macro-dynamics with all that good energy. That energy adds to the already pretty dynamic bass region which just brings a feeling of fun. Of course, changing the switch settings can add to or slightly take away from the level of dynamic energy you hear. However, even at its most dull settings the ZS12 Pro X is still a vibrant listen within the midrange. This is a very expressive sound albeit a little thin in some areas. It’s just another way to listen folks. Those dynamics are helped immensely but the way the staging is coordinated within my head space. I hear sound all around me with this set. Left to right, bottom to top and even some decent depth to the sound.
Lower-midrange
The lower midrange generally features mostly male vocals and from my perspective they come across very well and with great presence and nice chiseled edges. Maybe at times males don’t sound the most authentic or natural. Possibly a hair too candescent or a hint more uplifted than organic. That said, I don’t mind it one bit because males also have this lean sort of mass to them which hits the ear as density. That density makes male voices sound highlighted and polished. Males like Chris Stapleton in “Tennessee Whiskey”. I would have made a bet, without batting an eye, that his voice was going to be fuzzy, grainy, metallic and too edgy in his louder and fuller throated and ballad style moments. As so many sets can do when he’s really going for it. Boy, would I have been wrong. The reason being is that there’s just enough warmth from the bass region to give that body some slight measure of girth, which adds dimension to the sound, or some roundness. Beyond that, the lower-mids are just like the rest of the mix as they do have a certain smoothness to them. More like glass-lined than velvet and just another good way to listen to male vocals. Not everyone’s cup o’ tea, but nice, nonetheless. There’s some very nice texture to this region too which brings upon a palpable feel to each note. Yes, it has some issues and maybe won’t for everyone’s preferences tonally, but I cannot call it bad by any stretch.
Upper-Midrange
The upper midrange comes a bit more forward in the sound field by a slight margin. They are also more lifted, with more of a bright energy. I believe the pinna rise is roughly around 10-11 db’s which is a good place to be with a bass shelf that is also 10-11 db’s. Both of those depend heavily on what switch setting you use but I’m speaking in generalities. Anyways, the upper mids do have some well controlled sparkle, some slight sibilance as well but from my perspective that is the worst offense. Honestly, female vocalists & instruments have a nice timbre which is just off-natural. The timbre is enriched with some illumination across the region. Certainly not a warm, juicy, or dull upper mids. I hear more of an energetic and lively sound. All instrumentation comes with some added radiance. Females like Adele in “Hello” don’t come across quite as moody, emotional, but her vocals do come through crystal clear with a very nice presence against the rest of the melody. One track I always use for its versatility is “High” by Caitlyn Smith. The ZS12 Pro X is able to begin with soft inflections, good separation, her voice is flowery. As she heads into the chorus you’ll hear the energy greatly pick up. The ZS12 Pro X handles this songs chorus so we’ll for the price. Many sets will come across as just a fusion of noise while the ZS12 Pro X handles each modulation in her voice along with the chorus if other instruments very well. Now, it may be a bit too enlightened and bright for some. But that doesn’t take away from the skill of this set.
Downsides to the Midrange
I think one issue would be for those who really enjoy a milkier and richer midrange as the ZS12 Pro X is not the most “rich” or thick in note body. Some folks simply enjoy a warmer sound, more organic, closer to natural. Not that the ZS12 Pro X has anything at all to be ashamed of. I could also see some people wanting a hair less energy in the pinna area. I don’t feel it’s an issue, but I know plenty of folks who are very sensitive to any glare of any kind. Lastly, the ZS12 Pro X does have some slight sibilance from time to time as well as the slightest BA timbre at times too. Nothing that is an annoyance to me because I’ve heard so much worse from so many sets. I actually feel KZ did a wonderful job in bringing so much energy and dynamism to the sound while still retaining some naturalness within the timbre. Very nice for the price.
Treble Region
Looking at the treble region the first thing that comes to mind is the word “control”. The treble has very nice control of this area of the mix and at the same time manages an uplifted sound. Of course, the treble isn’t perfect. This set does cost $50. Still, for the cost I find the tuning to be very addictive over time and the treble is a huge player in that. I hear some good brilliance which adds this very uplifted and lustrous sheen to the sound. That sheen permeates down into the midrange bringing a sense of air and openness to the overall sound. Lately I’ve reviewed a number of warmer iems and I was ready for a change of pace. Something with a little more dynamic energy. So nice timbre for what it is and also nice coherence between drivers. Really a nice job of combining these drivers together while not having any glaring issues. This is not easily accomplished and so I say “kudos” to KZ. Nice work making sure the sound melts together with no real hiccups. The treble has a sparky nature with a kinetic feel to the sound, it’s textured and has at least some treble bite while keeping an otherwise smooth demeanor most of the time. Certainly, there will be those who want even more roundness in this region and even more brilliance, but I feel if KZ tuned any more emphasis I wouldn’t be anywhere near as happy as I am with it.
For me anyways
Beyond that, the ZS12 Pro X’s treble region shows off very nice detail retrieval. I found that to be the case as the transients come and go quickly as the attack through decay keeps things tight, very well controlled and without ever coming across as sloppy or just a mishmash of treble tizz. Also helping the detail emergence is the fact that resolution is great. KZ did this without it feeling like it’s forced or overtly bright. Something they used to tune their sets with. Those are days past folks. The ZS12 Pro X comes through brilliant enough whilst being able to bring all the little subtleties to the surface with ease. Now, there are some sets in the price point which are even more analytically tuned, with an even dryer, faster, and brighter tuning than the ZS12 Pro X. However, I think we can all agree that those types of sets have their own issues. I actually feel that the ZS12 Pro X carries a very nice treble tuning. Just enough body to notes, it’s a fast treble response, smoother than it is crisp yet not devoid of some crunch when needed, and plus… It’s also very well extended into the upper treble. With all that said, the best thing this treble has going for it is how well it controls a well emphasized treble without sounding off in its timbre. For me anyways.
Downsides to the Treble Region
The biggest drawback for most folks is that this is a bright treble. At least to a degree. It’s certainly not a warm or dark treble playback. There are so many folks in this hobby who don’t do well with bright things. It’s understandable too. I get it. However, I am one who has to listen to all types of sound signatures, and I’ve come to love and enjoy most of them. I can definitely enjoy what KZ did here on the ZS12 Pro X. Another area of concern may be that there is some sibilance which makes its way into some tracks. Again, just like the midrange… It isn’t bad, it doesn’t take over the overall sound and grab my attention. Just minimal at best as this is just a byproduct of a brighter treble using balanced armature drivers. By-and-large I find the treble to have a very nice timbre. There really aren’t many drawbacks’ folks.
Technicalities
Soundstage
This brings us to the soundstage. I’d say above average almost across the board. The ZS12 Pro X has a deep and extended sub-bass, lifted pinna and good extension past 10k. Usually this will signal a set which has a wide presence in its sound field. So yes, it is a wide stage that envelopes the listener. I do hear sound all around me as evidenced in the track “Hook” by Blues Traveler, a track I always use for stage size (well one of them). Once that harmonica begins the Melody stretches very wide, past my ears and the height fills up the sound field within my mind. Now, depth is only average. Of course, average is good, remember that. At least there is some depth of field. There is good layering of sounds so long as the track isn’t too complicated or bass heavy. Anyways, the stage size is very nice. I don’t think it’s class leading, but it’s up there.
Separation / Imaging
Separation of elements within an imaginary psycho-acoustically rendered stage are great! You have clean notes on this set, glass-lined note edges, good resolution across the board, faster transients and very good space and air to the sound. All of this “can” add up to a set that has good instrument separation. In the case of the ZS12 Pro X I’d say that’s exactly what’s happening. There is good space between elements of the stage, whether it be vocalists or instruments. Now, you may have slightly less distinct separation with more complicated and congested tracks. In fact, you will have less distinction. Also, in bass heavy jams where the low-end conquers the sound as a whole you’ll also not have as good of separation. Imaging follows separation almost to the tee. In my opinion anyways. Really good so long as it isn’t some crazy congested song.
Detail Retrieval
I feel you already know what I’m going to say here. The detail retrieval on the ZS12 Pro X is definitely above average. Very good for the price. For all the reasons the ZS12 Pro X separates well it also uncovers subtle details well. Now I don’t consider this set class leading in this category, but it is very well done. The ZS12 Pro X does have some smoothness, it isn’t all dry, crisp, and pristine. It does have some musicality to it. So, it isn’t perfect. However, I don’t think anyone will complain.
Is it worth the asking price?
This is another set where I won’t waste time explaining myself because absolutely the ZS12 Pro X is worth every last penny. I have a harder time wondering if this set isn’t one of the best iems that money can buy at the price it’s at ($50). It is a very well done iem in my opinion. Now, not everyone will share that thought and I understand that. Some people swore off KZ/CCA a while ago and will never touch one of their sets. However, I am not that guy as I have no feelings either way which means that I don’t miss out. Yes, this set is worth the cash and should be on everyone’s radar if the sound signature seems to suit you. It’s a dope set!
The Why…
First off because the build is ridiculously tank-like. Built to last, the ZS12 Pro X is made entirely out of a very robust zinc alloy which does make this set somewhat heavy, but also completely bold in all ways. Next, the design is one of the better designs on the market. Yes, we’ve seen similar shapes and the diamond plate pattern before, but man is this a cool looking set. The texture which covers them you can see which adds another dimension to the look and aesthetic. However, we don’t buy sets purely on looks alone as they also have to sound good first. Well, good for us because KZ made a set in the ZS12 Pro X that does look good but also sounds even better. That’s of course if you enjoy this type of sound.
That sound…
The low-end hits deep, authoritative in its forceful attack, clean in its tighter decay and well balanced across the bass region. This set has very good bass folks. Next is the midrange, which is clean as can be, highly resolute and detailed, great separation of instruments, nice stage to capture those instruments, and it is actually just as melodic as it is analytical. Just a well-balanced set dynamically across the board. Also, the treble has a great emphasis which plays off of the bass region very well. It has a nice treble bite, yet it also comes across smooth enough to not sound abrasive and I don’t hear any huge peaks that will kill your ears in treble shrillness. Imaging is pretty nice with a couple caveats, detail retrieval is very nice and the staging as a whole is wide, and even somewhat deep. It’s just a well-tuned set with a brighter hue but also plenty of oomph down low. Just a good $50 iem and one which should be on most lists going forward.
Ratings (0-10)
Note: all ratings are based upon my subjective judgment. These ratings are garnered against either similarly priced sets or with similar driver implementations or styles with the unique parameters of my choosing. In the case of the KZ ZS12 Pro X ratings below, that would be $35-$65 iems of any driver configuration. Please remember that “ratings” don’t tell the whole story. This leaves out nuance and a number of other qualities which make an iem what it is. A “5-6” is roughly average and please take into consideration the “lot” of iems these ratings are gathered against. $35-$65 US iems of any kind is a huge scope of sets, and it’s also extremely competitive. It should mean something to see a rating above a “9.0”, in my opinion. My ratings are never the same and each set of ratings tells a different story. Each time you read one of my ratings will be unique to that review. Basically, I create a Rating that makes sense to me.
Aesthetic
–Build Quality: 9.8 Built extremely well.
–Look: 9.6 Best design at the price?
–Fit/Comfort: 9.2 Good for me, not for everyone though.
–Accessories: – – –
–Overall: 9.5🔥🔥🔥
Sound Rating
–Timbre: 9.2 Great timbre for a $50 budget hybrid.
–Bass: 9.3 Nicely emphasized impactful
–Midrange: 9.2 Controlled, engaging, clean.
–Treble: 9.5 Clean, brilliant, detailed, extended.
–Technicalities: 9.2 Great technically across the board.
–Musicality: 8.5 Very musical for the tuning.
–Overall: 9.200🔥🔥🔥
Ratings Summary:
This is one of the most cut n’ dry ratings I’ve done in some time. I simply don’t see much to argue with here. Each one of these ratings holds water. In fact, I may have gone a hair low on some of them. I rated against any and all iems between the price of $35 and $65. That’s a ton of iems and probably makes up the majority of iems under $100. However, there simply aren’t many sets exactly like the ZS12 Pro X. There’s a few which are similar I suppose but none that does exactly what this set does. I chose this random price point because I was trying to think how I would’ve been looking if $60 to $65 was the absolute highest I could go with my purchase. I have about fifteen of those sets in front of me and many more in my collection that just didn’t make sense to compare against. Make no mistake though, there’s some bangers in there. Also, the ZS12 Pro X is not rated the best for me. However, it really is up there. Ranked amongst the best the price point has to offer, no doubt about it.
Explain Yourself!
Like I said, there really isn’t much to explain here. At least that I can think of anyways. However, every review seems to get at least one person bringing up the bass rating and so I suppose this rating will be no different. I gave the ZS12 Pro X a rating of a “9.3” in the “Bass”. I could definitely see someone saying that the quantity isn’t enough. However, that would be a basshead. I honestly can’t see anyone complaining that the ZS12 Pro X bass region is quality though. Also, it’s emphasized quite a bit. Anyways, the bass is always a Rating which gives me issues because everyone has a different idea about what “good bass” is. I would say that the only other rating that gave me pause was the “Musicality” rating. I say that because it’s a made up and subjective idea of what “musical” really is. We all have different ideas of what it means, and everyone is right because it’s what “musical” is to those people. So that rating is a bit ridiculous and one which could always go either way. Every other rating I stand by. They are locked in. Moving on…
Conclusion
To conclude my full written review of the KZ ZS12 Pro X I have to thank Keephifi for providing the ZS12 Pro X in exchange for a feature at Mobileaudiophile.com. I gotta say, this set surprised me quite a lot. It is a very competent and well done iem. I really mean it that if you are looking around its price point, don’t just pass by this set. Of course, it has some issues, and it is not perfect but… It is very good. So anyways, this has been a fun review and I really do hope it helps you to make a purchasing decision.
Other perspectives
Please check out other thoughts about this set. Not everyone has the same likes and dislikes, music library, audio gear or the same hearing abilities. Also, not everyone has been down the same path in audio too. We are just different. So please, do yourself a favor and check out other thoughts my friends. It can only help. That all said, I think I’m done. Please take good care of yourself and your family, stay as safe as possible and always… God Bless!
