KIWI EARS SINGOLO: Attempting Aiming Towards Neutrality

KIWI EARS IEMs are currently one of the most featured products here in my review content in both my own blog and in an audio forum site that I usually hangout and quite active in some topic threads. Since the KIWI EARS Cadenza, I've always been interested in its upcoming model releases ever since.

And now, KIWI EARS releases their latest entry-level IEM and it is also a collaboration with one of the most influential audio reviewers in YouTube, Crinacle. This is KIWI EARS SINGOLO and it is a single driver configuration IEM with some interesting passive resonance filter technology on it.

The SINGOLO has a custom 11 mm dynamic driver with LCP (Liquid Crystal Polymer) diaphragm that were sourced from Japan. LCP is known for its tensile strength and firmness for better transient response that conveys a clear and crisp sound while retaining its natural timbre and tonality. Aside from its dynamic drivers, KIWI EARS also implemented their own passive resonance filter called KARS (Kiwi Acoustic Resonance System) in which based on a Helmholtz resonance principle in which is an airflow resonance phenomena in a chamber that is also applied on both physics and acoustic engineering. In the field of acoustics engineering, the Helmholtz resonance is also applied in principle on bass-reflex Hi-Fi speakers and it is also known that our own mouth with some instruments like Jaw harp is practically a Helmholtz resonance. The KARS will improve and regulate the air pressure within its acoustic cavity to deliver a more consistent and solid bass response with a tighter and well-controlled deep rumbling sound.

The internals were encapsulated in a 3D-printed resin shell chassis that takes a shape on a standard UIEM-type mould. This form factor will give the best possible fitting for most ear sizes but its brass nozzle seems to be relatively short and stubby that might be problematic to some ears. It has a blue-ish hue with some glitters on its faceplate while it has a clear cavity base where you look upon the driver and maze-like acoustic tubing. Like all KIWI EARS models, this set has a standard 2-pin connector as its interchangeable mechanism.

As for fitting and comfort, the SINGOLO is quite fits well into my lugholes as it really rest comfortably without any discomfort issues, but for those ears aren't particularly suits well with short stubby nozzles, try eartip-rolling on this one, ear tips with long stem ones might work. Good passive noise isolation is possible to achieve as long as you have ear tips that will give you the best sealing.

About its stock cable that was included with  this set, it is relatively on the thinner side when it comes to texture and that said cable, while it is quite supple to hold, the quality isn't on par to some other IEMs in the same price range as some its competitors have thicker, better materials and resistant to entangling. The cable is probably made of silver-plated oxygen-free copper with a clear PVC-coated insulator with an L-shaped 3.5mm termination plug.

The product packaging of SINGOLO is quite elementary like all KIWI EARS sets in the entry-level segment. Even the quantity of accessories is fairly scanty just to cover some basics on using this set.

Here are the following contents inside of KIWI EARS SINGOLO's packaging box:

• Pair of KIWI EARS SINGOLO IEM transducers.
• Stock cable
• Three (3) pairs of black wide bore silicone ear tips in different standard sizes.
• Three (3) pairs of white narrow bore silicone ear tips in different standard sizes.
• User's manual

The KIWI EARS SINGOLO can be amplified with sources with decent power output in usual normal gain mode but to show its full potential and better dynamics, a better sources with better and more powerful Hi-Fi DAC/Amp would be a better choice for this set as it quite scales more on power.

In terms of tonality, these are some matters I should address that this set is quite ear tip-dependent as it influences the air conduction from its sound waves. Narrow bore ear tips will give a mild U-shaped  bass-boosted sound profile while the wide bore ear tips will give a tad brighter mild U-shaped sound. A third party ear tips like the Divinus Velvet will give a bit more of a balanced-neutral sound with some bass boost on it.

(Graph was provided by [USER=516219]@baskingshark[/USER], credit to his effort on this one.)

LOWS/BASS:

This bass section is probably the most prominent part of its overall frequency range. It's more focused on the sub bass part than the mid bass region as it has more reverberating with good depth and incisive bass response.

Like I mentioned regarding its sub bass presence, I clearly felt the reverberation and rumble from certain instruments like synthesisers, low tuned bass guitars and drum machines. Meanwhile on its mid bass part, I consider it as sufficiently textured although it sounds a bit hollowed on wide bore ear tips for some reason. Bass guitars sound sombre and resonant while double bass has a bit broader sound on it but if we use the wide bore ear tips, it sounds a bit dull and hollow. Bass kick drums have these rumbling and eerie sounds on every stroke, but again, using a wide bore on this one will make it sound rather hollow. On bass and bass-baritones, while they have a sufficient heft and some richness, they don't have that darker tone, sounds a bit too light that its doesn't have that plush and wool-like texture on their vocals but surprising I clearly hear to vocals ends which a quick vibrato that resonates well.

MIDRANGE:

I really thought that sounds too recessed at first impression but as I listened to it for a longer session, it has only some slight notch on the midrange presentation as it sounds clear, neutral and transparent as it was intendedly tuned. Mostly vocals and some of the instruments will sound clear and natural on this one and due its ear tip dependant ilk on it, narrow and balanced bore will give a tad fuller and texture sound on most male vocals and mostly on brasses and percussions while wide bore ones will give more emphasis on females vocals and woodwinds instruments.

Under male vocals, almost all types of voices of this particular gender will sound a bit too lean on wide bore ear tips. All of my sound character descriptions in this category will be based upon both narrow-bored and balanced-bored ear tips. Baritones have plush and smooth sound quality on their vocals while tenors have brassy, rich and emotive sound on them and then, countertenors have smoother, light and graceful sound. The contraltos which is a female vocal type will sound fare well on this type of ear tips as it will give more weight and richness on this particular vocal type. On female vocals, narrow and balanced bore ear tips will somehow give more smoother, golden and velvety on mezzo-sopranos while sopranos will sound more creamy, emotive and rich on their voices. Wide bore ear tips will make them more lively and fervid on mezzo-sopranos while it adds more silvery and gleaming on sopranos.

On instruments, narrow and balanced ear tips will give a fuller and organic sound on brasses and percussives that I will describe briefly on each individual instrument.

Brasses:

Trumpets - Sounds full and rounded

Trombones - Fairly solid and dramatic sound

Horns - Velvety albeit a bit mellow.

Percussives:

Tom-toms - Resonant sounding with sufficient warmth

Snare drums - Has a hard and penetrating sound.

Tenor drums - Sombre and sonorous sounding

Kettledrums - boomy and rumbling although a bit mellow.

I also want to add cellos on this one too despite being a string instrument, it has a sonorous, silky and calming sound in which I consider it as a natural with its tonal note versatility.

In wide bored ear tips, it appears that it added some emphasis on timbre definition on woodwinds and some string instruments.

Woodwinds:

Concert Flutes - Mellow, rich and brilliant sound

Piccolos -  A tad penetrating and shrill sounding.

Clarinets - Too vivid and shrill sounding.

Saxophones- Reedy and incisive sounding.

Strings:

Guitars - Quite balanced and some buttery, some tracks with acoustic guitars sound more crisper and dry sounding.

Violins - Vibrant, brilliant and a tad metallic sound on every motion on its bowstrings.

Harps - Resonant, sharp and metallic sounding.

The sound of the piano of this one is quite well-balanced and pretty even tone so as to maintain a consistent timbre on its note keys while having an articulate resonance and sufficient rich and sweet tone.

HIGHS/TREBLE:

Again, I will bring up its ear tip dependent state of this set as it somehow truly affects the treble response from each type of ear tip bore. Wide bore will give a tad more brighter sound that the elevation on upper-mids up to the brilliance part of the treble region will give more crisp, detail and definition on vocals and attack of instruments but at expense of having a shrill, piercing and intense sound that might be bothersome to most treble sensitive folk.

Both narrow and balanced bores will give smoother, evened and well-balanced treble response but there's a caveat, it loses some energy and clarity while it lessens the shrill and piercing sound on vocal and instrument definition.

Both ear tips won't give us that airy treble extension on its brilliance and moderate sparkling sound (narrow bore ear tips will even lessened but not to the point of being a dull sounding). Cymbals will sound lustrous and resonant while hi-hats have its short full and buzzing on its distinctive chicky sound. On percussive chordophones like glockenspiels (keyboard) and celestas, the former has a sufficient shimmering and lustrous sound while the latter one has a mellow and sweet sound.

SOUNDSTAGE, IMAGING AND OTHER TECHNICALITIES:

It seems that technicalities aren't SINGOLO's strongest asset given how it performs in this aspect as it projects a rather intimate head stage dimension. It has a fairly average sound field size as it has median lateral span, average height ceiling and less depth on its overall sound/speaker stage.

On its stereo imaging, it projects a typical two-dimensional presentation in a less defined layering of frequency and dynamic tones of instruments and vocals that it somehow affects the separation performance. So playing a complex track with multi-instrument performance will be less appealing on this set.

Coherency of its dynamic driver appears to be excellent in this regard as it is able to execute a fast and responsive transient performance without any distortion. Resolution capabilities on this one is rather a mixed bag as it is one of the less resolving single dynamic driver IEM I've ever tested. Its micro-detail definition is rather blunted that it is quite inadequate to retrieve some details and nuances from an audio track but its macro-dynamics appears to be decent on its compression.

PEER COMPARISONS:

EPZ Q1 PRO

• Like the SINGOLO, this set also has a single dynamic driver and a shell chassis made of resin but it doesn't have some special features like the KARS on the SINGOLO. Its 10mm dual chambered dynamic driver has a composite diaphragm composed of PU and LCP materials, and it was encased in a more compact UIEM-type resin shell chassis. Compared to the SINGOLO, the quantity of inclusion is relatively meagre but at least it has a storage pouch in which the former doesn't have one and also the stock cable is a bit better.
• The EPZ Q1 PRO has more coloured tuning as it has a U-shaped sound profile with a bit of warmth of its overall tonality. Compared to SINGOLO, this set has a more punchy bass response, a reasonably textured midrange which is more flexible on vocals and instruments in terms of timbre and tonality, and a smooth and less airy treble presentation. On technical capabilities, this set has a bit more spacious head stage in width, height and depth in a concave-like stereo imaging presentation in a not so well-defined layering on its soundscape. But at least, compared to SINGOLO, this one is more resolving in both macro-dynamics and micro-detail capabilities.

EPZ x TIPSY STAR & ONE

• Another set with similar construction build with SINGOLO as it also has a single dynamic driver set-up and it also encased in a resin shell chassis, but difference are that like its Q1 PRO cousin, it has composite diaphragm on its dynamic driver, its resin shell chassis is pretty more compact in size, and similar quantity of included accessories inside of its packaging box.
• STAR & ONE has a U to V-shaped sound signature (depending on gain mode) as it has more well-bodied bass response, a tad warmer but more midrange presentation and a brighter treble response as it has more sparkle and airy treble response. On its technical performance, compared to the SINGOLO, this set has a wider sound/speaker stage, similar stereo imaging presentation, it has satisfactory layering and separation, and its overall resolution capabilities is a bit better.

KEFINE DELCI

• While it also has a dynamic driver configuration, it was encased in a metal alloy structure which is made of aluminium alloy. Inside of its dual cavity dynamic driver, it has a composite diaphragm made up of DLC and PU material. The DELCI has better included accessories as it has a sturdier stock cable and a storage case.
• The DELCI's tonality has a warm U-shaped that makes it relatively an analogue-ish sound profile. Compared to the SINGOLO, it has more coloured sound as it has more punchy and tactile bass, a warmer and textured midrange for fuller and lush voices especially on male vocals and brass instruments, and also smooth and inoffensive treble presentation although it has a moderate airy extension. On its overall technical performance, this set can project an average to above average sound/speaker stage, a concave-like spatial stereo imaging in decently layered soundscape with fairly separation of instruments and vocals, and a similar resolving capabilities with the SINGOLO in terms of micro-dynamics.

As I concluded this review, this is one of the sets that doesn't have that impact in my initial testing but as the test goes by with some modifications like ear tip rolling, I understand and got some idea on what particular tuning that this set is aiming for if you got the proper ear tips to put into it. That KARS technology that was implemented here is probably its selling point and somehow it really works.

Once again, to sum up this assessment, the KIWI SINGOLO is definitely one of the sets that will be on the side of “acquired taste”  type of tuning in which might be pleasing to the ears of some audio enthusiasts who seeks uniquely tuned set (Fortunately, I am also that kind of audio enthusiast). But regarding the quality and quantity of accessories, I hope that KIWI EARS will improve in this category as they are still quite elementary and rudimentary on this one.

KIWI EARS SINGOLO is exclusively available only in LINSOUL, you can check out the non-affiliate link below.

★★KIWI EARS SINGOLO - LINSOUL★★

For more KIWI EARS products, here are some of the previous product reviews on the said company.

■ KIWI EARS CADENZA

■ KIWI EARS QUARTET

■ KIWI EARS QUINTET

■ KIWI EARS FORTEZA

■ KIWI EARS MELODY

SPECIFICATION:

MODEL: KIWI EARS SINGOLO

IMPEDANCE: 32Ω

SENSITIVITY: 106L8dB

FREQUENCY RESPONSE: 20Hz – 20KHz

CABLE LENGTH: 1.2M

PIN TYPE: 0.78mm 2-PIN CONNECTOR

PLUG TYPE: 3.5mm

DRIVER UNIT(S): (1) DYNAMIC DRIVER

PROS:

● Lightweight yet solidly built resin shell chassis.

● Aside from better sub bass presence, The KARS also minimises some occlusion effects thus driver flex issues will not occur.

● Quite an ear tip-dependant as it affects the sound quality output.

● While it can be amplified with sources with decent power output, this set scales well on better power output with high gain mode as it doesn't sound distorted at all.

● It includes two types of ear tips inside the box.

● Clear sub bass presence with a fairly texture mid bass while maintaining a clean bass response.

● Neutral, transparent and tidy midrange presentation.

● Smooth and inoffensive treble response.

● Not a hint of harshness and sibilance.

CONS:

● Quality of its stock cable.

● Included stock ear tips will not give you that intended tuning of this set that you need some third party ear tips.

● A bit hollowed mid bass (stock ear tips)

● Lean and recessed midrange (stock ear tips)

● Absolutely not for treble heads as it doesn't have that brightness on its treble response and also, treble air is rather modest in my opinion.

● Lacklustre on its overall technical performance.

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*

P.S.

I am not affiliated to KIWI EARS 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 Ms. KAREENA TANG for providing this review unit. I truly appreciate her generosity and trust towards me and other reviewers.