What does 50USD get you nowadays?!
*The rating is comparative with IEMs in the same price range, that is up to 100USD.
This set was kindly sent to me by KeepHifi. Many thanks! My impressions, biased as they might be, are my own.
KZ ZS12 Pro 2 is a 12 units/side IEM, with the following breakdown of the drivers (from KeepHifi website). It sells for 60 USD and is available here. (Unaffiliated link)
The impedance is 35Ohm and the sensitivity is 109dB, according to the same source.
The unboxing is exactly that, you take them out of the box. That’s it! In the plain cardboard box, you have the IEMs in a foam insert, a 3,5mm terminated cable and some tips. Just like the ZX10 Pro 1 and 2 before.
The construction is much to my liking. While the first ZS10 Pro looked good, it had very sharp and rough edges. Frankly, a bit of a hazard to handle them. This was fixed with ZS10 Pro 2, that had better finish and added some switches. I do not care for switches, so those are not my favourite. ZS10 Pro 2 takes things one notch further. They build quality is very good, I cannot find any problems. At least nothing appeared during the testing and I do not see any signs of problems developing soon.
*The rating is comparative with IEMs in the same price range, that is up to 100USD.
This set was kindly sent to me by KeepHifi. Many thanks! My impressions, biased as they might be, are my own.
KZ ZS12 Pro 2 is a 12 units/side IEM, with the following breakdown of the drivers (from KeepHifi website). It sells for 60 USD and is available here. (Unaffiliated link)
The impedance is 35Ohm and the sensitivity is 109dB, according to the same source.
The design of the front plate is a continuation of the ZS10 Pro series, but also a nice hint to the UM Mest Jet Black, with that golden screw at the apex. Personally, I quite like the design. The shells are transparent, letting you see the neat arrangement on the drivers inside. One cool touch is the logo inside the shell. It is, of course, only aesthetic, but nice to see the attention for this kind of details.
Straight out of the box, with the stock cable they sounded quite...uninviting. The voices and, truly the whole upper-mids section seemed distant and unengaging. The treble had some air, but not nearly enough for me. The bass was also lacking in quantity and quality. Straight from a dongle, albeit a good one, the iFi Kensei, they sounded flat, both in tuning and staging.
I have then changed the cable from stock to a pretty expensive one, the FA Venom. I know, I know, this costs 20 times more than the IEM itself. To add insult to the irony, I have tried them from a very good DAP, the LP P6P. I realize people buying the KZP12 won’t use it with this crazy combination, but hear me out. There are many reasonably 4,4mm priced cables and most people might already have one. The ISN G4 is one such good alternative that I had at hand.
After some burn-in, and for the purpose of this review, I have returned them to the stock cable and used mostly cheaper sources, mainly dongles.
Once the burn-in has been completed, they sound more open, bassier and a bit larger. Brain burn-in must have played a role, for sure. I needed time to adjust down from the sets I usually listen to.
One thing that might be important, they have a semi-open back design, which means there is significant sound leaking out of them when listening, even at low volume. This is not a set to listen to next to someone on the sofa (well, unless they are listening too, in which case it is irrelevant).
Let’s take a closer look at their sound...
Bass is muscular and well-articulated, I’d say one of the highlights of this set. The extension is good, with only a minimum amount of roll-off. The quantity of mid-bass is not huge, but nothing is lacking here though. The level of details is average, but I reckon it is ok for the price range. The decay is good, the bass is nimble but not necessarily thin. Moving towards the mid-bass, it is equally well articulated, not very detailed, but with that pulsating breath-like sound. Not bad.
Mids start to show signs of weakness. The lower mids are a bit on the thin side, which, on one hand lets the mid-bass shine, on the other it exposes the real problem, the upper-mids. The latter are harsh, and they tend to stick out a bit. With calmer, goth-music, this is like a sore thumb. The entire atmosphere is dented, the way light takes away your dark adaptation. Male voices sound distant, but this can be fixed with cables and sources. They too, could have used more body. Katatonia, for example, sounded, at times, like the voice was distorted (at high volume). A bit of sibilance was present, but not in an amount to pose a problem. It’s not all bad news though, the same harshness that makes the voices a bit too husky, lends a hand with the distorted guitars. In my book, lack of texture in the mids is a capital sin. KZP12 redeem themselves with a fairly gritty guitar tone. Clarinet is another instrument that takes full advantage of this texture. Too many IEM makers have polished this area way too much, which works fine for many genres, but it’s not exactly to my taste.
As the volume goes up, things start to sound less coherent, the upper-mids get an additional boost compared to the rest and the overall sound is brittle and not always pleasant.
Treble is another highlight of this set. It’s not the most resolving I have heard in the 50USD segment, but it is very good nonetheless. It is reasonably detailed, airy and with impressive extension. If the music is chosen carefully, it can reward you with a pleasant sound, but for some combinations, it is overshadowed by the upper-mids. Lower the volume a notch and the composure is regained. Cymbals have a natural sound with good body, but are not the most detailed. This is a second highlight of the set. Yes, it lacks the sparkle of the Letshuoer C4, but it makes up for it in natural sound...
Comparisons:
My plan was to compare them with the ZS10Pro and ZS10 Pro 2. However, they are clearly superior to these, in such a way that a full comparison makes no sense. Over the ZS10 Pro, ZS12 sounds bigger, larger, more bass and much improved definition. Over ZS10 Pro 2, better clarity, better instrument separation, better treble, more clear mids, even though the voices are pushed further one step (the curse of larger stage).
I have settled then, for the Hidizs MK10. It’s a single DD, at the price of 65USD compared to the 60USD for ZS12 Pro 2. A fair comparison, I’d say. I will only compare the sound quality and not the packaging or accessories. You will see from time to time a special guest, a glimpse into what 3-6 times the price gives you. Just for perspective.
The Ocean – Jurassic/Cretaceous
Wonderful percussion in the first part, a lot of LR effects before the guitar sets in, and well after. It is easy to follow all the multiple lines of the song, the separation is good for something at this price. You have the high-hats in the upper left, the bell of the ride in the far right corner, with bass around the base of the stage, a droning sound and plenty of other elements spread out nicely and evenly. There is a calmer passage at the 7 minutes mark, with a booming bass that sounds detailed and a flurry of cymbals (a little less detailed), before Renske comes in. Pretty hypnotic and the cymbals are exquisite, despite missing some sparkle. The body is nice and thick. Once it picks up speed again, it may sound a bit crowded, but still pretty respectable. That you can have such a good sound at 50USD is mind boggling.
Once more MK10 offers a more engaging alternative, with less bass, but with a nice mix of control and elasticity, that promotes it on top of my preferences for this piece. I prefer this kind of music with less bass and more grit. This is exactly what MK10 delivers here. A bit more detail in the treble, although the body is not as thick, the cymbals sound thinner.
We truly live in the golden age of audio.
If you are wondering what 300USD can get you, Dita Project M is a lot more detailed. As in , a lot. A whole new level of hi-hats is opened and the cymbals are expressing themselves in a much larger space, with many details. There is more sub-bass, which adds a bit of heaviness to the distorted guitars and to the voice. The quite passage is much clearer than before, the bass is more articulated, more textured and it hits like a hammer. The stage is larger, and the voices sound more natural. The drum fills move seamlessly from left to right.
Do not be disappointed, Project-M, despite it’s low price stands tall and pride in the pantheon of IEMs that are experts at metal. In typical Dita fashion, these are very coherent IEMs, with droves of details and good balance of gritty instruments and sweet voices.
Elton John – Home again
The upper-mids here are critical. They do a very good job, the piano sounds reasonably natural, the voice has good texture, not overly polished to lose its graininess, but not husky either. Enough as to sound natural. The waves are clearly audible and the sensation of a piano on a beach is strong. The tiniest hint of sibilance is present, but if you are not particularly keeping watch for it, you won’t hear it. The percussion sounds deep and calm, the cymbals that appear towards the end are in perfect harmony with the rest. Often, these simple songs can reveal more issues than the complex arrangements. The mids are depressed, but in a tasteful way.
MK10 does a good job too, either of these two being a viable option for this kind of music. The voice is closer, more lively, but just a bit thin. ZS12 with its hybrid driver array, did a better job at filling the body of those mids. The piano is also affected by this thinness; the timbre is a bit skewed towards the higher register. Hard to choose a winner here, let’s go with ZS12, for the more serious tone.
Fear of the Dark – Conki
Bass, Bass, Bass....this is just a test of bass and bleeding into other territories. Nothing to complain about here, the bass stays put and leaves enough room for the voice and treble. The Voice is clear and the underlaying L/R effects are quite noticeable. Balanced approach, putting to shame even big houses.
Bold, open sound with Mk10. As expected, the bass has more initial impact, but the reverberations die out quicker (faster transients). It is not the same rock-splitting force, and with the reduced instrument separation, it lags behind ZS12 Pro 2. By a hair, it might even come down to personal preferences. For me is a tie, I am not a big fan of big boomy bass, so I can listen to either with the same pleasure.
Let it go – Floor Jansen
It takes a special IEM to enjoy Floor’s powerful voice to the max. Especially since on this song, she really let’s it go...an amazing performance. The voice sounds clear enough and detailed. It is vaguely lackluster in body and sparkles and it leaves me wanting for more volume, more intimacy. The composure is kept throughout the song and the guiding line offered by cymbals is maintained in focus, despite the rest of the stuff that is happening. The bass has that live performance quality, authoritative, muscular.
MK10 renders the voice more intimately, more in line with the way I like this song. More engagement, more of a live performance feeling. The voice is energetic and shiny, with the tiny details just a bit shaded compared to ZS12 Pro 2. I think the issue here is the cymbals, more energetic than ZS12 and thus distracting the attention a bit from the voice details. I prefer MK10 for this one.
Like a woman can – Halestorm
Excellent test for shoutiness. In general, well controlled, the voice is kept loud and textured, but not too loud, you can feel the rage in Lizzy’s voice, the urgency of the drumming. Frankly, it could have been any of the songs from this album, but I chose this one for its apparent simplicity. The muscular bass guitar mirroring Lizzy’s voice, the granular guitar, all elements are present. The voice is a bit disengaged, as if coming from a distance, but this keeps it from being too loud. Again, a little, just a little harshness in the upper-mids and treble is the only fly in the ointment.
MK10 sounds just a little bit too bright. Not in a bad way, but in any case, there is a hint of sibilance, which is in general well kept in touch, only rearing its head at brief moments. The voice being freed from the action of the instruments, sounds more detailed this time, while the guitar solo is one mean piece of work. Alas, the bass is too fast and leaves the stage a bit exposed.
Mauvaise foi nocturne – Fatal Bazooka feat Vitoo (Pascal Obispo) Let’s have some fun, shall we?! I strongly recommend you to watch the video of this masterpiece of parody (ok, watch first the Diams video). This touches the limits of ZS12, the bass is strong and well balanced between sub and mid-bass. The mids are surprisingly good, with voices being clear and words easy to understand (the fact that I’ve watched the video 247 times helps, no doubt). However, upper-mids and treble is just a bit harsh, you cannot increase the volume without limit, it becomes bothering at some point. However, I can reach levels well above my normal, without any problems. Just be warned, if you are a high volume listener, it may be bright in certain combinations.
MK10 scores extra points for engagement, but loses some for excessive brightness. The bass cannot really keep up with the ZS12 Pro 2. Voices forward means you don't have to raise the volume so much, so that brings an unexpected advantage. It’s a tie, as much as I love the crystal clear MK10 for metal, it is not the best combination for this song.
The bass does not have quite the same reach with the MK10, and the amplitude is somehow capped compared to ZS10 Pro 2, but the transients are slightly faster, the impact of the bass being more decisive and thus feeling more nimble. The extra brightness does not bring much here and neither does the “dirty” mids. It’s an easy point for ZS12 Pro 2.
Special guest: AAW Z06 (a 300 USD, dual dynamic woofer+4BA). Another world. Bass is boomy, descending very low, both impact and extension are better than either of the other two. Impact is also improved. It is amazing how the bass is much more powerful while not bleeding at all into the mids. Almost subwoofer-like. The voices are clear and the treble is slightly depressed, allowing to increase the volume to dangerous levels. Exceptional clarity and large stage, doubled by good instrument separation. These are utterly engaging, leaving both ZS12 Pro 2 and MK10 in the dust. Their mids are a bit too polished, but for EDM and or/hip-hop, these are the thing to beat under 500.
MK10 sounds more enthusiastic, with about the same stage, but less instrument separation. It does make up for it in coherence. No matter what, single DD will always sound good to me. It sounds brighter than ZS12 Pro 2, there is more clarity in the mids and the bass feels to extend more on the sides of the stage. The sound is granular and gritty, the way I like it, with the voices a bit closer to the center. Overall resolution is better on the ZS12 Pro 2, but MK10 is more engaging. Win some, lose some, eh?
Conclusions:
KZ ZS12 Pro 2 is first of all a great achievement in manufacturing quality for a low price. Yes, you will find better manufactured IEMs, but at what price. KZ’s own Tourbillon Pro is a clear step up, but it is also more expensive. The finishes are top notch, no sharp edges this time and the IEMs are light and comfortable (a trait carried over from the ZS10 Pro series).
Sound wise, they are a moderate W shaped IEM, with decent, but not extraordinary sub-bass, focused more on precision than power, better than average mid-bass, good lower mids an upper midrange peak that is a bit too elevated for me and a treble that has the energy and the body but not quite the details. Good trade-off, if you ask me.
Where does it shine, well, my specialty, metal. Their mids carry enough texture and paired with something like the excellent RU6 dongle, they are veritable chugging machines.
Vocals are of above average in quality and body, but a bit remote, which, depending on your preferences, might be annoying or not.
I think for 50USD they are a very good proposition and if you liked the ZS series, these tick all the right boxes. It's a wonderful companion for the beach or sports, as you don't have to care that much about sweat/dust/sand, etc.
Thanks for reading!
