Introduction
KZ or Knowledge Zenith is the infamous brand that is impossible to ignore as they are everywhere and hate it or love it, they are here to stay. As per usual of their style or production, they are still very active in producing a wide range of earphones in a budget mindset and they have a mixed reception mostly due to their tuning, but as the times goes on, KZ is evolving and seems to be heading into the right direction with their current releases such as EDC pro, Hydro, Castor and many more that have a much more mature tuning that is pretty well accepted in the community. As we are heading towards the quarter end of 2024, KZ has decided to update their ZS12 series with the all new ZS12 Pro X which includes their famed super linear dynamic driver in this setup encased in an all metal build.
KEEPHIFI has been a good sport for sending us a pair of all new ZS12 Pro X for an honest take and we are grateful for this opportunity. They are the official reseller for the brand KZ and many more budget Chi-fi so do check them out for amazing deals. So, has the tide really turned for KZ with their current tuning ways? We shall find out here.
Functions & Specifications
Before we start the review, here are the specifications of the KZ ZS12 PRO X;
- Drivers: 10mm Super Linear Dynamic + 2 xDual 31736 Balanced Armature + 30019 Balanced Armature
- Shell: Aluminium Alloy Shell
- Frequency: 20-40000 Hz
- Sensitivity: 106dB
- Impedance: 25Ω
- Pin type: 0.75mm
- Plug type: 3.5mm
- Cable type: Silver-plated cable with or without mic
- Cable length: 120±5cm
The KZ ZS12 PRO X can be purchased at KEEPHIFI (Free delivery over USD30) via their website and also their shop in AliExpress for a plethora of Chi-fi products with great prices;
Packaging & Accessories
The ZS12 PRO X comes in a miniature, barebone packaging that has a rather budget looking package that is similar to the other KZ products. They seem to simplify the packaging to lower the cost to consumers as well as having minimal impact to the environment which is great. Inside we are greeted with 3 pairs of starline silicone eartips, a pair of KZ slow rebound PU eartips, a warranty card, a silver plated cable that users can choose with or without mic and the IEM itself. No case or pouch is included which is sad but understandable from their pricing. They are available in 2 variants, tuning switch variant and a stock version which is what I have in hand now. The tuning version costs slightly more but users have the freedom to tune the units via 4 switches to better suit their taste.
Design
The ZS12 PRO X design is actually superb and it might be one of the more premium designs from KZ encased in an all metal shell with a matte faceplate adorned with techy lines and a gold screw to complete the look. It is truly a looker indeed and they have a solid weight that makes it feel like a top shelf product on hand. The other side of the shell is a smooth metal body that has a different feel than the faceplate and they fit snugly in the ear concha. The edges feel smooth and the shell assembly is almost seamless which is a great step up from KZ finally showcasing their decades of experience. The IEM has the usual 0.75mm inversed 2 pin like any other of KZ models.
The faceplate line has some metal mesh in it and shining a light through it, surprisingly, we can have a look into the innards which makes the ZS12 PRO X an open back IEM. There is another pinhole vent near the nozzle and no driver flex in present.
The nozzle size is medium to large size (6mm diameter) with a slightly long nozzle and they are fitted with a fabric mesh in white. The nozzle now is now a part of the inner plate and that remedies the older version model problem where the nozzle might get detached after a while due to a separate nozzle design.
Inside, the ZS12 PRO X is packed with 6 drivers a side with a single Super Linear dynamic driver that has linear vibration response that is actually famed from their previous products for their great performance. The other 5 drivers comprises KZ’s own custom balanced armatures with 2 sets of 31736 (dual BA in one) and a 30019 mid-frequency balanced armature situated at the nozzle.
The cable is a KZ’s own basic silver plated cable and nothing much can be said about this cable as it is a basic cable.
Gears Used for Comparisons
FiiO Q7
Hiby FC6
Questyle M15
FiiO BTR7
Dunu Luna
Hidizs MS3
Dunu EST112
Moondrop A8
Intime Sho DD
Rose Technics Star City 5 Pro
KZ EDC Pro
Intime Sho DD
Letshuoer S15
Songs list
Tone and Presentation
The tone of the ZS12 PRO X is a mild V tuning that isn’t as aggressive as their previous models with a more controlled lower region and a slightly less peaky high range though still a strong high range. It has a bright tuning that has some warmth in the lower mids that gives a livelier overall sound along with a decent wide dynamic range typical of a hybrid setup. They are indeed an energetic performer with a bold sound but manages to be in control this time around as tuning improvements are made from the feedback from the previous ZS12 PRO 2 while still keeping their aggressiveness. Technicalities here are mediocre at best but they still have a good degree of overall details and clarity with minor coloration, competitive in their price range.
Soundstage
The ZS12 PRO X soundstage is actually good as they have a slightly diffuse field type of sound that gives an airy presentation probably due to their open back design. It is not humongous but very competitive in this price range with a wide and tall soundstage that doesn’t feel boxy or having a detached sound. They also do have a good 3D spatial sound that is accurate and immersive at the same time which is typical for a hybrid IEM. They are suitable even for gaming if you can handle a strong high range sound presentation.
Separation and Timbre
Separation is average on the ZS12 PRO X and they are a well tuned hybrid IEM that has good cohesion with all the drivers working well without any major gaps present. Crosstalk here has no major issues with the left and right sound well presented in a good stereo manner and a balanced setup will bring this setup a step higher. As for timbre, it is piercy, aggressive and bold with their great bass amount along with the extended, strong high range that give an ultra energetic sound that is borderlining sibilant. The balanced armatures used do exhibit a metallic sheen mostly in the upper regions and they can be unnatural especially with female vocals and high staccato sound but it isn’t a deal breaker for casual listeners.
Drivability
Rated at 25 ohms with a 106 db sensitivity, they are relatively easy to drive though need a slightly higher than normal volume and sounds great on whichever output you plugged it to but a good source matching is important here as a bright source may incur more fatigue with their high range. A warm source like AKM or Cirrus Logic based setup will suit them exponentially well. They do scale up with better sources but only marginally and they are not as forgiving in nature as they do show minor flaws in badly mastered recordings and they do sound better with high bit rates tracks which can be great for critical listeners. They are quite a sensitive IEM and can pick up noise from noisy sources so an addition of an impedance adapter can be used for these situations.
The Bass (Low)
The bass here using the famed Super Linear dynamic driver produces a neutral bass that has a good mid bass lift to give a strong impact in the overall bass performance and they are an authoritative bass when called upon but without any overpowering issues. The bass has a good amount of details present with a decent clarity without any muddiness or bleed present and an upgrade from the slight bass bleed present in the previous version. Resolution here is great with a clean and clear bass with a tight bass response along with good texturing that gives a clean overall bass presentation. The bass has decent extension with a good amount of air present giving a wide dynamic bass presentation that has a good airy presentation. Sub-bass has a good amount and extends pretty deep while possessing a good, strong rumble that is clean and meaty. The bass amount here is strong and may suit light bassheads but those seeking for an excessive amount of bass might find themselves wanting more as the bass here is just mildly stronger than usual.
The Mids
Midrange here is a neutral mids with a slightly forward sound that has a mild thickness and they tend to lean more towards the higher mid range therefore producing a bright-ish overall sound. The amount of details here is superb and they excel in the macro and micro details with a clear overall sound. Clarity is great with everything sounding clean and clear across the whole frequency but transparency here suffers a little by being slightly unnatural especially with their towards the high range as the balanced armature driver does sound a little dry and shouty at times. Resolution wise they are good for their price range with a good vivid sound and possessing mild coloration for a sweeter midrange. Vocals here are great as they do possess a good dose of brilliance that gives vocals a livelier effect that works especially well with female vocals albeit slightly sharp at times and for male vocals, they sounded deep along with a clear tone that is quite enjoyable. Instrumentals sound clean and clear but with certain higher range instrumentals like violins and saxophones tends to sound a little unnatural.
The Highs
The high range has a boosted range that has a rather obvious pinna gain to provide a bold high range with a very well extended frequency. They do sound a tad sharp but not as sharp as their predecessor that sounded harsher than this version and they have a good air present that gives a wider feel. With certain tracks and source, they do display some occurrence of sibilance and sound a tad peaky but I can see some treble heads will find these highs quite enjoyable as they possess a good amount of treble intensity tuning that is lively and packed with foot tapping energy vibes. Details and clarity here is actually rather good as they do possess a balanced armature trait of being clean and clear with every high note presented very well. Resolution here is good but transparency is average at best mostly for their metallic sheen from the balanced armature drivers but in return, they do possess a crisp decay which gives a nice bite in their presentation.
Comparisons
VS Rose Technics Star City Pro 5
The recent 1 dynamic + 2 balanced armatures hybrid from Rose Technics, the Star City 5 Pro and they are priced almost twice the price of the ZS12 Pro X but the packaging of the Star City 5 Pro is miles ahead with all the necessities needed plus an inclusion of a high quality audio dongle. Build quality of both is similar but if an all metal build you are seeking, the ZS12 Pro X is the one. Both have a V shaped sound but the Star City 5 Pro does sound more refined without a BA timbre and they are less sibilant.
Midranges on both of these sets do have a mild recessed midrange but the Star City 5 Pro mids have a thicker tone with a smoother upper midrange. Details on both are similar but clarity seems to be clearer on the ZS12 Pro X. Resolution and transparency is better on the Star City 5 Pro and they have a more intimate sound versus the more open midrange of the ZS12 Pro X.
Bass quantity on the Star City is bigger and deeper along with a better extended sub-bass response while the ZS12 Pro X bass is leaner by a small margin. Both have a similar tight bass but the ZS12 Pro X bass has slightly better texturing. Details and clarity on the bass of the Star City 5 Pro is cleaner and clearer.
Soundstage on the Star City 5 Pro does sound wider and taller but only marginally but the ZS12 Pro X does possess more air in their presentation.
VS KZ EDC Pro
The EDC Pro is on the the more recent single dynamic driver IEM that houses a similar Super Linear Dynamic driver that cost a measly USD10 (RM 40) and they have a similar dynamic driver that’s in the ZS12 Pro X. The build of the ZS12 Pro X is miles ahead and they do have a wider dynamic range but the timbre of the EDC Pro is more natural with better cohesion due to a single dynamic driver setup. Both have the same barebone packaging with the same basic cable but the standard 0.78mm 2 pin on the EDC Pro does have more benefits.
Highs on the ZS12 Pro X are stronger highs that possess more presence than the EDC Pro with a crisper and has a more evident sparkle. Details and clarity is also better on the ZS12 Pro with better air and texture. Highs on the EDC Pro do sound smoother and they have better extension along with more transparent highs that have better timbre.
The Midrange of the ZS12 Pro X has better clarity and details while the EDC Pro has a more balanced midrange without any upper mids peak. Vocals on the EDC Pro do sound more natural but lack brilliance like on the ZS12 Pro X and the details and clarity is also better with better micro details.
Bass on the ZS12 Pro X has a tighter slam and they have a slightly bigger bass quantity as well as in the sub-bass region but only in a small margin. Bass texture is quite similar with a clean and clear bass on both sets. Clarity seems to be better here on the EDC Pro.
Soundstage in the ZS12 Pro X is wider, taller and airier but only by a small margin.
Synergy
FiiO Q7
My go-to portable DAC/amplifier is the Q7 for benchmarking. It is a transportable powerhouse when it comes to driving power and they are packed with all the main features you will need making them a good DAC amp in terms of power. They have superb driving capabilities with a well controlled sound for in-ears and can bring out a lot of details for some IEM. The KZ ZS12 Pro X doesn’t need this huge amount of power but it does give a good sound refinement by providing a good overall improvement in their dynamics.
The bass the Q7 provides here is tighter, cleaner and clearer but no amount is added. Sub-bass does dive deeper with a more evident rumble that increases the immersiveness of the IEM. The bass resolution does sound more vivid and they have an airier bass that makes the bass more fun to listen to. Bass seems to roll off slower at the end giving an extended response.
Midrange has a slightly thicker sound and possesses better resolving capabilities along with slightly better detail retrieval. Resolution has improved but transparency seems to be the same. Upper midrange does sound less shouty and smoother but marginally. There is some improvement in their spaciousness that gives a little more room in their midrange. Vocals sounded slightly more accurate with the smoother upper mids.
High range sounds mostly the same with a strong presence and the same balanced armature timbre but they do possess an airier presentation along with an extended response. There is some refinement that gives a smoother sound that mitigates the peaky sound but only a little.
Soundstage is wider and taller with an accurate placement while increasing air.
Questyle M15
The Questyle M15 is no doubt my favourite portable DAC/amplifier with Questyle’s own direct current amplification and they are a neutral to bright sounding device that possess great efficiency with a good driving power for their size along with superb power efficiency. The M15 does possess a great extension and they are packed with details on both ends displaying none of the Sabre chip glare and they do well in refining the higher range of the gears used.
Bass sounded cleaner with added details and clarity along with a tighter response. The bass does not add in quantity but it has a wider overall response that sounded more accurate. Sub-bass depth remained mostly the same but they do sound cleaner and clearer with a more controlled rumble.
Midrange sounds mildly thicker and they are able to give a cleaner sound while providing better transparency and resolution but the upper mids still have splashes of peaks. Vocals sound more natural with a slightly more open with a lusher mids.
High range sounds mostly the same but they do have a better sparkle. Treble remains mostly the same with a slight reduction in their metallic timbre. Details seem to remain the same but they do sound clearer with slightly more refined highs and a slight increase in their extension.
Soundstage has increased in width and height and they do add some spaciousness.
Who Is It For?
The KZ is a suitable IEM for those who seek an bold, energetic and bright sound that possesses a great overall detail retrieving set along with a wide frequency range that is typical of a hybrid IEM. They possess an airy sound that doesn’t have a boxy sound and they are an aggressive and fun set to listen to. Users who seek a good high range energy or treble heads will find this ZS12 Pro X an amazing set for their strong high range and that being said, those who are treble sensitive might want to steer away as they are borderlining a sibilant sound. They are also suited for gaming and movies as well for their immersive low end but aren’t suited for bassheads. They are more suited for instrumentals, EDM, Hip-hop and modern musics but not suited for vocals for their balanced armature timbre. They are also suited more towards a fun, engaging listening instead of a critical listening or monitoring as they may come as unnatural to say the least.
Final words
So has KZ turned the tides with their hybrid just like they do with their dynamic based IEM? I would say they are almost there as they do sound good in terms of providing a superb energetic sound but with minor caveats like exhibiting some balanced armature timbre that might impact the naturalness of sound and some refinement is needed in the high range. But in terms of technicalities for their price range, they actually do fit the price range for their great overall details retrieving qualities as they really do sound clean and clear along with a superb bass response deriving from their Super Linear Dynamic. I believe with some fine tuning of their balanced armature, they would be a killer in the hybrid segment as they seem to nail the build quality right this time with their solid all metal casing and not to mention, their ultra budget price. I would like to wish KZ nothing but the best in their evolution and I believe 2025 will be a year for KZ to solidify their name in the big/budget leagues.
I would rate this product a 4 over 5 stars.
Pros
- Decent overall technicalities
- Beautiful, solid open back design
- Good fit and lightweight
- Good width and depth soundstage
- High quality aluminium shell
- Energetic, bold and fun sound
- Wide dynamic range
- Good cohesion and separation
- Great overall details
- Wide dynamic range
- Accurate, immersive and organic bass
- Engaging midrange with good brilliance
- Lively, crisp high range
- Airy overall sound
- Decent resolution
- Amazing value for 5 drivers IEM
Cons
- High range a little peaky and splashy
- Aggressive treble
- Mediocre transparency
- Midrange might sound thin
- Barebone packaging
- Balanced armature metallic timbre
- Not clinical enough
- Overshadowed by KZ lower range products
- Basic KZ cable
