KOTORI AUDIO ZEPHYR: A Reminiscing Neutral Tuning

Zephyr/Zepherus one of the four main Anemoi or wind gods in Greek mythology and he is the Cardinal Wind God from the west. It is said that he is the bringer of spring season and a producing breeze that bears fruit during this period. This is where the word “Zephyr” is derived from which means gentle breeze.

This is my first product review from an audio company, Kotori Audio and this one is based from the land of Merlion, Singapore. Kotori previously released some products like the single dynamic driver set, Dauntless and the Vampire which is a single balanced armature driver IEM.

The item that will be featured here is their latest model, the Zephyr and unlike previous models, it is a hybrid driver configuration consisting of a dynamic driver and balanced armature driver. The dynamic driver of this one is 10mm in diameter and its diaphragm was applied with titanium coating for a stiffer and longevity of the membrane for better transient response as it will deliver a cleaner and denser bass response. And then, it was paired with a full range balanced armature driver from Knowles which handles the midrange and high frequencies for clearer, detailed and high resolution sound for vocals and instruments.

Aside from the drivers, it is working in tandem with some interesting technologies like Acoustic Balancer Tube which is somewhat a passive pathway of acoustic tube in which well-integrated into the cavity of its 3D-moulded shell structure with balancer tube to regulate pressure control for more consistent response of its dynamic driver while lessening any chances of occlusion effects a.k.a. driver flex. The shell chassis of the Zephyr is on a compact size and it is composed of composite materials as its cavity base is made of resin while the faceplate is a CNC-milled aluminium alloy chassis with a modernist Bauhaus aesthetic. It uses a 0.78mm connector as its interlocking mechanism for its detachable cable.

The stock cable that was paired this one is a 2-core 28 AWG OFC Silver-plated Litz Copper that were sheathed with PVC wire insulation and its termination plug is an angled gold-plated single-ended 3.5mm. This one is quite supple to hold and flexible enough but it is susceptible to entanglement. At least I don't encounter any microphonic issues on this one.

The Kotori Zephyr is quite sufficiently packed with accessories that can be useful for every listening usage.

Here are the following contents inside of its packaging box:

• Pair of Kotori Audio Zephyr IEM transducers.
• Stock cable
• 3 pairs of H-01 silicone ear tips in different standard sizes.
• 3 pairs of M-01 silicone ear tips in different standard sizes.
• Ear tips rack
• Metal alloy carrying case
• Paperwork like instruction manual and warranty card.

On power scaling and amplification, this set is easy to drive and it can be powered up by devices such as smartphones (with 3.5mm jack), laptops and tablets which usually have a normal gain power output. But pairing it with better sources with hi-fi grade DAC/amps like DAPs, headphone DAC/Amp dongles and desktop DAC/Amps will push its full potential to sound more dynamic and fuller.

The Kotori Zephyr definitely has a neutral, nearly linear sound profile as if there are almost exaggerated peaks on its overall sound quality. Although this set is also an ear tip-dependent as it changes its profile into a more of a U-shaped sound signature on narrow to balanced bore ear tips.

LOWS/BASS:

It appears it is more focused a bit on mid bass texture rather than on sub bass presence as it adds note weight on some bass-clef instruments as it has sufficient punch and tactility with some tidiness of its overall bass response. The sub bass seems to have decent definition on how it delivers a satisfactory reverberations and rumbling presence from sub bass-focused instruments like synthesisers, drum machines, octobasses and low tuned bass guitars and double bass instruments but it has a less depth on it.

On how the mid bass texture quantity affects the tonal colour and to some extent, sound characteristics on some selected instruments, bass guitars sound resonant while the double bass has some heft and raspiness on their notation, and then bass kick drums have sonorous and thudding sound on every stroke. As for deep male vocals, basses have reverberating and resonating vocals but it sounds a bit less darker in which to give a more dense and full voice while on bass-baritones, as it has that resonant and acceptable rich sound on their voices, it still doesn't have an ideal timbre that these type of vocals should have due lack of volume and fullness.

MIDRANGE:

It appears that this is a main feature of this set on how it presents this particular frequency section and let me explain about this one. The midrange presentation of this one is presented in a neutral manner with sufficient warmth, transparent and clean sound which makes it quite versatile on both male and female vocals and also, all types of instruments.

On male vocals, baritones have rich and smooth vocals, tenors have a clear and a bit brassy warm sound on their voices, and then an emotive, captivating and tender sound from countertenors. Regarding the female vocals, contraltos have rich and plush sound from their chesty vocals, mezzo-sopranos have velvety and coppery sound on their vocals, and then, soprano vocals have a silky and crystalline sound on them.

As for instruments, on the string instruments, guitars sound more balanced and midrange-y as it has an enough crisp, cellos have a cantible, warm and silky sound, and violins have sensuous and calm sound on every motion on its bowstrings. On woodwinds instruments like piccolos, concert flutes, clarinets and saxophones, the piccolos have clear and graceful sound but sounds a bit less brighter, the concert flutes sounds soft and mellow, clarinets have a caressing and warm sound, and saxophones have a sonorous and sombre sound. When it comes to brasses, trumpets sound warm, trombones and horns. Then on percussives, snare drums sound clear and precise, tom-toms have an ample warmth with resonance sound, field drums sound sonorous and kettledrums have these resonance and deep sound on them on every stroke. Pianos seems to have an even and mellow tone as it has that rounded and sweet sound albeit I find it a bit dull in some piano tracks.

HIGHS/TREBLE:

The treble response of this one appears to be even and balanced as it presents a smooth and a relaxed presentation albeit there's a hint of dryness and sterile sound on it. Some positive takes on this one as it doesn't have any unwanted peaks in the upper-mids and presence section that it guarantees no sibilance nor harshness. It has a sufficient clarity and definition for delineation on vocal and attack of instruments.

It is observable that it has a rather modest airy extension on its brilliance part and less sparkle that affects on some treble-focus instrument's tonal characteristics. Cymbals have a undulating and a tad dry sound while hi-hats have a short buzzing sound, glockenspiels sounds on the lustrous side of tone and celestas have a sweet and mellow sound.

SOUNDSTAGE, IMAGING AND OTHER TECHNICALITIES:

The overall perceived sound/speaker stage dimension of this one is on the average size as it has median length of lateral span with satisfactory height ceiling and a rather decent depth as it gives me an intimate head room within my aural sphere.

The imaging presentation in this one projects  a two-dimensional stereo presentation with adequately layered tones and dynamics of vocals and instruments in clean, black soundscape in which I can pinpoint and panned out some of its points across its perceived spatial sonics with an acceptable separation on each element.

Its hybrid driver set-up has some cohesive and homogenous performance that's its dynamic driver is pretty responsive on its transients along with a clear and detailed sound of its BA driver without distortion or any phasing issues. Its general resolution capabilities of this one seems to be middling as it has a solid macro-dynamics but its micro-detailed retrieval seems a bit less sharp on its extracting some subtleties and nuances from an audio track.

PEER COMPARISONS:

SIMGOT EM6L

• This SIMGOT model shares some similarities with Zephyr as it also have a composite shell chassis and a hybrid driver set-up but there are some differences.
• This one has more driver counts as each side is equipped with 1 single dynamic driver and 4 balanced armature drivers and it uses a QDC-type bi-pin connector as its interlocking mechanism.
• The product packaging of this one is quite conservative in terms of quantity that it only includes a single type of ear tips.
• The tuning of this set has a usual Harman-style of tonal profile veering towards a U-shaped sound signature.
• It focuses more on sub bass focus bass response, a leaner and recessed midrange presentation and tad brighter and more airy treble response.
• On technical capabilities, it has a wider sound/speaker stage projection with similar performance on layering and separation although this set is quite more resolving on resolution aspect especially on micro-detail.

EPZ K5

• This is an initial-level midrange offering from EPZ and like the Zephyr, it also has a usual hybrid driver configuration.
• While it shares some driver set-up similarities but there are some differences as the K5 has more quantity drivers and its BA driver uses Sonion and its shell chassis is almost entirely made of resin with laminated wood on its panel.
• This one is also well-packed with accessories and it has a modular termination plug feature on its stock cable.
• The K5 has a mild U-shaped sound profile with some emphasis on upper-mids up to the high frequencies.
• As for its general tonality, it has rumbly and impactful bass response, a slight notched midrange presentation but it has an ample warmth, energetic and transparent sound for females vocals, woodwinds and string instruments, and bright, airy and shimmering treble response.
• Technicality-wise, this set can project an above-average sound field in a well-layered three-dimensional stereo soundscape with a more resolving on resolution capability.

AFUL EXPLORER

• Another hybrid driver IEM offering comes from AFUL in a comparable price range and it also has a similar driver configuration.
• This set has a single dynamic driver and two custom-BA drivers with some proprietary tech inside and it was encased in a 3D-moulded resin shell chassis.
• The AFUL Explorer is also well-accessorised and it has a better stock cable in my opinion.
• This set also has a neutral-type of sound profile but it has an elevated low frequency while the rest of the frequencies were in all neutral presentation.
• The bass response of this one is quite more tactile and punchy, a sufficiently warm and well-balanced midrange presentation that makes it more of an all-rounder for vocals and some instruments, and then, a smooth and balanced treble presentation which shares similarities with the Zephyr.
• On technicalities, in regards to sound/speaker stage size, it has similar width but it has better depth, a more holographic stereo imaging presentation and a more solid macro-dynamics when it compares to the Zephyr.

As I conclude this product assessment, The Kotori Audio delivers a set that was the midrange-level tuning of mid 2010's in which I really liked but it was quite expensive at that time, and now, after almost a decade,  we finally have the Zephyr which has almost exact sound profile at cheaper and more affordable price. For sure that it has some  drawbacks particularly on the technical performance and its tuning might be too flat to some listeners but for audio enthusiasts who have some particularity on tonality particularly on midrange-focus ones, this one will be a perfect match for them to track vocals and instruments.

Kotori Audio Zephyr is now available on Kotori's official store. Check out the link below.

LINK:

https://kotoriaudio.com/products/zephyr-iem?srsltid=AfmBOooN7kP3As8Zpt1sR6LEXH5DhfAyWnXeMRpzTH_TMB50SRgTrMDS

SPECIFICATION:

MODEL: KOTORI AUDIO ZEPHYR

IMPEDANCE: 18.3Ω

SENSITIVITY: 92dB

FREQUENCY RESPONSE: 20Hz – 20kHz

CABLE LENGTH: 1.2m

PIN TYPE: 0.78 2-PIN CONNECTOR

PLUG TYPE: 3.5mm,

DRIVER UNIT(S):  (1) DYNAMIC DRIVER + (1) BALANCED ARMATURE DRIVERS

PROS:

● It has a composite shell chassis which is quite light and comfortable to wear.

● The Bauhaus-inspired aesthetics will surely be appreciated by audio enthusiasts with minimalist taste.

● Good quality stock cable.

● Fairly well-accessorised for its asking price.

● The tuning that this set conveys somewhat eerily similar to the old midrange set which sounds neutral and linear especially for audio professional use.

● Punchy and precise bass response.

● Excellent midrange quality as it delivers a well-balanced, clean and transparent presentation.

● Clear and delineating on vocals and instruments’ tonality and timbre.

● Smooth and gentle treble response, a good recommendation for treble-sensitive folk.

● Scales well to any portable multimedia devices even with decent power output.

CONS:

● Technical performance isn't its strongest point as it has a perceived average sound/speaker stage, two-dimensional stereo imaging with just an acceptable layering on its soundscape.

● Noticeably lack of sub bass rumble

● Absolutely not treble heads due to attenuated upper mids up to brilliance treble region that is sound less shimmering and just a modest amount of airy extension.

● Those pointy edges might cause some minor paper cuts.

TRACKS TESTED: ( * = 16-bit FLAC, ** = 24-bit FLAC, *'* = MQA, '*' = DSD, *'= .WAV)

Alison Krauss -When You Say Nothing At All *

Jade Wiedlin - Blue Kiss**

Led Zeppelin - When The Levee Breaks **

Mountain - Mississippi Queen *

Queen - Killer Queen **

Guns N' Roses - Patience *'*

Eric Clapton - Tears in Heaven '*'

Sergio Mendes- Never Gonna Let You Go '*'

Pearl Jam - Daughter **

Roselia - Hidamari Rhodonite *

Assassin - Fight (To Stop The Tyranny)*

Celtic Frost- Visual Aggression *

New Order - Blue Monday *

The Corrs- What Can I do (unplugged version) *

Jimi Hendrix Experience - Voodoo Child *

The Madness- Buggy Trousers *

Metallica - Motorbreath **

Mariah Carey- Always Be My Baby *

Destiny's Child - Say My Name *

Malice Mizer- Au Revoir *

Mozart - Lacrimosa *

New York Philharmonic Orchestra - Dvorak- Symphony 9 " From the New World." *

Eva Cassidy - Fields of Gold (Sting cover)*

Michael Jackson - Give In To Me *

Exciter - Violence and Force *

Diana Krall - Stop This World **

Debbie Gibson - Foolish Beat *'*

The Sisters of Mercy – Lucretia My Reflection**

Suzanne Vega – Luka **

Lauren Christy – Steep *

Ottoman Mehter - Hucum Marsi *

Diana Damrau - Mozart: Die Zauberflöte*

Type O Negative - Black No.1 *

Felix Ayo - Vivaldi: Presto **

Three Tenors - Nessum Dorma *

Mercyful Fate - Witches' Dance *

P.S.

I am not affiliated to KOTORI AUDIO nor receive any monetary incentives and financial gains as they provide me a review unit for an exchange of factual and sincere feedback from yours truly.

Once again, I would like to send my gratitude to RAY TAN of KOTORI AUDIO for providing this review unit. I truly appreciate his generosity and trust towards me and other reviewers.