Affordable, Well Executed Closed Back Planar Headphones

2025 has been another great year for Chi-Fi especially in the midrange sections, blasting out highly competent audiophile gears from the likes of Ziigaat, Letshuoer, Hidizs and of the one we are focusing today, Kiwi Ears. Their emergence has been swift and impactful with their unique, bold ideas of products that don’t skip on their performance indeed. Releases such as the Septet, Astral, Airoso, Ètude in the IEM realm to the Ardor, Altruva and Ellipse in the headphones arena, displayed a performance that is rarely heard of in their price range. Now, they are back with a unique collaboration with the famed Zeos Pantera or Z Reviews with one of his first headphones collaboration, the Kiwi Ears X Z Reviews Serene. It houses a custom planar with a closed back design that is suited for travels as well as on a desktop setup. A good closed back planar is a rarely seen product especially in this price range of 159USD and the Serene certainly intrigued me indeed as coming from experience with Kiwi Ears, they might potentially be a hit product. So how will they perform in this rather loose territory of closed back planar headphones? We shall find out here.

But first, a huge gratitude to Kiwi Ears for the opportunity by sending us a sample of the Kiwi Ears X Z Reviews Serene and no monetary transactions or affiliation is garnered for this review for an honest take on these headphones. Review is done solely by personal opinion.

Functions & Specifications

Before we start the review, here are the specifications of the Kiwi Ears X Z Reviews Serene

• Driver Information: Custom 72mm x 89mm Closed Back Planar Driver
• Impedance: 50 ohms ±15% at 1kHz (DC)
• F0 / Lowest Resonant Frequency: 130Hz ±20%
• Sensitivity: 102dB ±3dB (at 1kHz, Test Voltage: 0.179V)
• Rated Power: 10mW
• Maximum Power: 20mW
• Test Frequency Range: 20Hz–20kHz
• Voltage: 0.57V
• Total Harmonic Distortion (THD): Less than 3%

The Kiwi Ears Serene can be purchased at their website and many other platforms around the globe like Linsoul.

Kiwi Ears x Z Reviews: Serene

Packaging & Accessories

The packaging here is simple indeed with a hard paper box with a decent modern theme and information printed on the back. Nothing really special here as the focus of the Serene is mainly on the product itself. Inside we have some paperworks, a nylon sleeve 3.5mm braided cable to dual 3.5mm for the headphones and of course, the headphones itself. For the price considering it is using a planar, it is acceptable but a choice of 4.4mm termination is more welcomed.

Design

The design language here is simplistic and it does have a rather modern, matte black design with deep purple metal parts design that doesn’t really bring attention which can be good for outdoor usage. The cups are made from high quality polymer that feels sturdy with a CNC aluminum faceplate that has grooves like a vinyl in purple. The hinges are made from solid aluminum alloy with swivels on both sides for a more compact storage as well as better fit adjustments that suit even DJs on deck. The Serene is not a collapsible headphone that can be folded for a more compact form factor for storage but their footprint is small and lightweight.

The headband length can be adjusted to fit even big heads and they are tightly secured which is great as they seem to be well built. No weird, annoying creaking noise is present once the headphones are worn. The top headband has a 2 layer built where vegan leather is used on the top side with Kiwi Ears and Z Reviews stamped on it and the inner part has a smooth vegan leather that has some padding in it. The headband does feel solid and they have a rather minimalistic design that is lightweight. The ear cups are made from vegan leather as well with a thick, memory foam padding that is very comfortable. The size of the earcups are quite small but still able to cover my whole ears to give a superb, passive isolation. No left right indicators on the body of the headphones, instead the indicators are printed on the insides of the earcup’s foams.

Driving the Serene is a custom made, proprietary 72mm x 89mm planar magnetic driver which is rather small but they are actually quite efficient and they are able to produce a big sound that rivals conventional sized planars. Being a full closed back design, Kiwi Ears has implemented a proprietary refractory filter to absorb the rear sound waves guiding the sound towards the user’s ears.

The Serene has 5 holes for the driver venting situated at the top outer part of the earcup and they provide some breathing room for the driver to prevent driver flex as it is a known issue for planar drivers. There is a slight pressure build up that doesn’t interfere much with the comfort and that shows how much isolation we get from these headphones.

The cable included is 4 core oxygen free copper and only available in 3.5mm. The cable has a soft nylon sleeve that is pliable with a nice y-splitter with Kiwi Ears branded on them. The plugs are made from metal and the terminals are gold plated. Pretty standard cable but it does feel well made and looks great but an extra choice of balanced plugs will be great nonetheless.

The cable included is 4 core oxygen free copper and only available in 3.5mm. The cable has a soft nylon sleeve that is pliable with a nice y-splitter with Kiwi Ears branded on them. The plugs are made from metal and the terminals are gold plated. Pretty standard cable but it does feel well made and looks great but an extra choice of balanced plugs will be great nonetheless.

Gears Used for Comparisons

Songs list

Tone and Presentation

The tone of the Serene is a classic V shaped sound that has a big bass presence with a good amount of energy on the treble. The midrange isn’t too recessed but due to the boosted highs and lows, they can be perceived as recessed. The tone of the Serene is quite balanced and they do lean slightly towards a brighter side of the spectrum while possessing a warm, musical and intimate sound that is fun to listen to without sacrificing technicalities. The overall sound is rich with a great amount of details and they are able to provide a superb clarity in their overall presentation which is typical of a planar driver.

Soundstage

The Serene soundstage is quite mediocre but given the price and its closed back system, they are actually quite decent with a wide and tall sound that doesn’t feel closed in when compared to earphones or earbuds. They are wider than tall and do perform like a near field monitor that focuses the sound straight to your ear instead of dispersing the sound field, producing an immersive, lively sound but it does lack air and space albeit marginal. Headroom here is spacious although it being a closed back design, the Serene has a medium headroom with no major boxiness and when driven properly, they are able to expand wider. In terms of accuracy, the Serene possesses a holographic soundstage that has a good 3D spatial awareness with directions of sound easily distinguished, making them suitable headphones for gaming as well as movies. All being said, the Serene soundstage is still a step wider than IEMs or earbuds with a bigger headroom and they aren’t as intrusive with their fit like IEMs.

Separation and Timbre

Separation here is great and punches above their asking price here as their imaging and layering is presented clean without being congested. Having zero crosstalk issues contributes to a wide dynamic range that separates the left and right sound in a good, accurate stereo width. Timbre here is actually great as they don’t display the usual planar metallic timbre, instead they are accurate and natural sounding really close to a dynamic driver in this region. Timbre here is best described as punchy, rich, lively and full of energy.

Drivability

While rated at 50 ohms with a 103db sensitivity, they are slightly tough to drive but don’t need a dedicated full desktop setup to perform to their best with adequate volume. A simple dongle setup actually isn’t sufficient to provide a loud volume and the dynamics are rather suppressed but a better, stronger setup does scale them up quite significantly especially with desktop setup. Source matching here does slightly lean towards a neutral sound with a mild bright tone in my preference to give a better amount of overall clarity but may also match warm sources to give them a more silky, smooth sound depending on your preference. The Serene is a pair of headphones that is rather forgiving with a mildly revealing sound as they aren’t picky in the types of files being played but they do benefit from a good mastered track marginally making them a suitable pair of headphones for a casual usage that can also be passed as a monitoring set.

The Bass (Low)

The bass is a push north of neutral of the spectrum with a punchy, authoritative, meaty and energy packed but in an amount that doesn’t give overpowering problems that causes bleed or bloat. There is a healthy dose of mid-bass lift that contributes to the boosted bass but they are well in control. Details here are good with superb clarity as they have a clean slam that is tight and clear with a good texture that shows layers on the bass pretty well without any muddiness. The pace of the bass is fairly quick and they are lively to listen to with an ability to handle fast, bassy tracks with no issues making them a good pair of headphones for EDM and modern pop. Sub-bass here dives deep with a strong, clean rumble that complements well with the lifted mid-bass, completing a full bass response. Although having a boosted bass, the amount here is big but I do feel that the Serene isn’t a pair of headphones for bassheads as the bass here doesn’t provide a shaking, vibrating type of bass and the overall sound is quite well balanced juggling between quantity and quality fairly well.

The Mids

Midrange on the Serene is a neutral flat mids that is perceived as slightly recessed due to being overshadowed by the boosted low and highs but they still have the presence without being too pushed back. The midrange here has a smooth, warm sound that has a great amount of detail and they have a good clarity without any masking effect or bleed coming from the bass. The Serene possesses the ability to show macro and micro details well with a lean towards the former that gives a superb clarity that is highly resolving alongside adequate thickness of body. There is some colouration present to give a more vivid, fun sound but in return, their transparency here is average but they do not possess any weird, plasticky sound that planars might exhibit. The Serene performs well in vocals especially with female vocals as they are tuned to have a great amount of brilliance in the upper mids and they are indeed lush, bright with a lively sound that is very enjoyable. Male vocals perform great as well but at times with deeper voice notes, they tend to lack body and depth in a small margin. Instruments sounded mostly natural but it may occasionally display some colouration that hampers the accuracy like strings and drums.

The Highs

The high range here is a neutral with a boost at the 10kHz above to give the highs a good amount of air and presence. The high range does have a mild boost to give the overall sound a lively presentation that is energetic with a bite and it is an enjoyable listening but at loud volume, they might exhibit some fatigue in the long run. Details here are superb and every high note is clear as day which is typical of a planar based high range. The highs are sparkly with some crispness in their decay that gives a more enjoyable highs while having a rather natural high range. There is some aggression in the type of highs here but they are able to sound relatively smooth without being sibilant or harsh but with some bright sources, the high might get a tad piercing. Treble here has good intensity that gives an energetic presence with a push in clarity in their overall presentation. Treble sensitive users might want to take note as the treble is certainly not for those who seek a laid-back, relaxing type of sound, instead are for those who like a bold high range that has the presence with some bite. Surprisingly for their high range timbre, they don’t have the metallic timbre typical of a planar driver and they are relatively natural and accurate but it still isn’t as natural as some conventional dynamic drivers out there.

Comparisons

VS Beyerdynamic T50P (299 USD)

The Beyerdynamic T50P is actually a replacement bought by me to replace my spoilt DT1350 that has been my go-to portable headphones for long travels. The T50P shared the same DNA for being a well implemented, miniature closed back dynamic headphones that isolates really well and is also suited for DJs or monitoring purposes. They are an L shaped sound that focuses on the high range as opposed to the V shaped sound of the Serene. The T50P small size is a supra-aural type that leans on your ears and the Serene is a circum-aural where it covers the whole ears, that being said, for a long usage, the Serene is more comfortable and the thicker memory foam really helps too. The T50P does come with a storage case and the build seems to be more solid as they are more costly but the absence of replaceable cable really is a let down.

The high region of the T50P is slightly more present and has a sharper, brighter sparkle that gives more air to the music while the Serene does sound crisper and less offensive. Details are better on the T50P but with similar clarity. Timbre does sound slightly better on T50P with a more organic accuracy. Trebles on both have an intense type but the amount seems to be bigger on the T50P and the Serene manages to sound less aggressive.

Midranges both have a similar neutral signature but the T50P has a more forward approach and they aren’t recessed like the Serene. Details are slightly better on the Serene while clarity remains similar. Although having slightly recessed mids on the Serene, they have more space and air. Both of these sets are highly resolving with a dash of colouration on the Serene but transparency does go to the T50P. Vocals on the Serene sounded sweeter while the T50P sounded more balanced.

Bass quantity on the Serene sounds bigger with the same amount of mid-bass lift as the T50P but the Serene dives deeper along with a bigger sub-bass response in a small margin. Details and clarity of the bass is better on the T50P but the Serene does sound more immersive with a bigger headroom effect.

Soundstage on the Serene is wider with an airier presentation possibly due to the bigger planar driver.

Verdict: Serene is more comfortable with a more fun signature that isolates similarly with the T50P and costs way less but the T50P is more accurate with easier storage capabilities.

VS Audio Technica ATH-M50X (199 USD)

The famed, legendary DJ and monitoring headphones from Audio Technica Japan are more mainstream headphones that are well received for their value in comfort and sound. They do cost slightly more than the Serene with similar comfort levels but the technicalities here on Serene does trumps the M50X especially in the overall clarity. The M50X does look cooler and a wider range of designs are available suiting a wider taste of users. As for build, the Serene does feel sturdier as the M50X does have some creaking sound coming from the hinges which are made of plastic. Both cables can be replaced but I do favor the Serene for the dual side mono cable for balanced connections but the single input on the M50X is more user friendly especially with DJs.

Highs on the Serene is stronger with  more energy along with an extended, airy and crisp presentation versus the flat, smoother highs of the M50X that is less intrusive. Details and clarity is better on the Serene here along with more resolving highs but the M50X does have a more natural timbre. Treble on the Serene is more intense and they gave the edge in the overall clarity.

The midrange of the M50X is slightly more resolving with a slight forwardness to them but clarity and details are better on the Serene. The M50X does possess a thicker mids with a tad more colouration that leans towards the lower range while the Serene sounds clearer and cleaner with a more upper mid range brilliance. Vocals on the Serene sound livelier but a little distant due to the boosted lows and highs.

The bass quantity is similar in amount but the Serene sounds bigger and punchier with a more nimble, quick bass with extra energy. Details on the Serene here are cleaner and clearer while clarity on both are similar. The sub-bass on the M50X had a bigger rumble but the Serene does have a clearer, cleaner sub-bass.

The soundstage on both are similar with a wide, spacious sound that possesses great air but the headroom on the Serene feels bigger.

Verdict: The Serene has the better value of both with better overall technicalities but the design and brand of the M50X does interest mainstream users out there.

Synergy

As for synergy, personally I would recommend neutral to bright sources like some Sabre or Cirrus Logic based chipset as they will add a touch of clarity and also push up the midrange to give a more balanced overall sound. A warm source from the likes of AKM and some well tuned Burr Brown will give a more laid-back sound but it does exacerbate the coloration a little more and that can be unnatural sounding at times. The Serene do respond well with amplification and they do need some juice to get going, so giving a good, powerful source but power will scale the Serene up producing better overall dynamics and a more controlled, textured bass as well as smoothening the high range but on certain sources, only on loud volume, there is clipping on the bass. As for file selection, the Serene isn’t really a revealing set of headphones but it does make certain low quality sources like bluetooth and low bitrate tracks sound a tad compressed only marginally, albeit audible. For monitoring purposes, it is doable but there are plenty of headphones that specialise in this area. Their superb isolation and comfort does make this a great set for DJs, while their great immersive sound is suited for gaming and movies.

Good matching: Neutral desktop setup, Qudelix T71, Hidizs S8 Pro, Questyle M15, 7HZ Artemis39, FiiO Q15

Not so good matching: EPZ TP35, FiiO KA3, Dunu DTC100

Who Is It For?

The Kiwi Ears Serene is a recommended choice for those who want to experience a well tuned, natural planar that is suitable for both indoors and outdoors usage. It is probably one of the best portable headphones of a planar driver with their speed, richness, clarity and energy. They are fun sounding headphones that possess good technicalities with a punchy, energetic sound and will suit audiophiles as well as mainstream users. Their mild V shaped sound will match modern genres such as EDM, pop, hip-hop and even jazz but not so much for metal, JPop and harsh genres as it will get spicy for treble sensitive users. For monitoring purposes, they aren’t a neutral reference type of sound but they are still an accurate sounding pair of headphones. The Serene is usable even for workouts, gaming and movies for their comfort that has an immersive sound but for those in warm weather, they will cause heat after a prolonged usage as they are a closed system.

Final words

The Kiwi Ears Serene has certainly found a niche alongside Z Reviews in the entry portable level closed planar segment as they are a stable sounding pair of headphones with the good traits of a planar driver without any major setbacks like the unnatural timbre. They are relatively easy to drive although some power is needed making them good starter headphones for those who want to enjoy the richness, speed and technicalities of a planar driver. Though the sound might be a little aggressive for purists out there, they are  an enjoyable pair of headphones that are suitable for casual listening. The build is solid with great comfort with a small footprint but they can’t be folded and a carrying case isn’t provided. That being said, the Kiwi Ears X Z Reviews is a solid choice for those who want a less intrusive fit like earphones while still having superb isolation alongside great sounding planar headphones without breaking the bank. Thumbs up Kiwi Ears.

I would rate this product a 4 and half stars over 5 stars.

Pros

• Good technicalities with superb musicality
• Solidly build
• Superb memory foam comfort with no driver flex
• Great passive isolation
• Great separation, imaging and tonal balance
• Great overall clarity and details
• Good timbre for a planar driver
• Decent headroom and soundstage
• Energetic, punchy, extended bass
• Good, controlled sub-bass and mid-bass lift
• Clean, lush and warm midrange
• Great amount of brilliance
• Good resolution
• Energetic, sparkly, crisp high range
• Well extended vivid treble
• Relatively easy to drive and match
• Superb price versus performance index

Cons

• Not a neutral pair for critical listeners
• Slightly recessed midrange
• High range may lack transparency
• Not for treble sensitive users (subjective)
• Carrying case not included(nit-pick)
• Design a little lacklustre (nit-pick)
• While the cable is nice, no balanced termination are available
• With bassy sources and loud volume, bass will start clipping (nit-pick)