DUNU SA6 MK.II: Almost Flawless, Exquisitely Refinement

"The starting point of all achievement is desire." 

--Napoleon Hill, American writer and author of Think and Grow Rich.

That's how I tried to do my best on doing some product reviews on other portable audio devices for the past months and yet I'm still yearning and having some lingering desires that I really want to test the Dunu SA6 again. And here it is, the Gods of Audiophilia smile upon me and grant my craving not just only to test the DUNU SA6 but its evolved variant which makes me even more fortunate (though I'm quite a sceptical and very irreligious person).

We already know the reputation of DUNU as a company, so let's cut to the chase on it as I will pinpoint more on its tonal and technical specifications regarding this particular product. Be prepared as this product assessment might even take a bit longer to read.

This is DUNU SA6 MK.II, this is DUNU's latest flagship offering in the midrange segment. This is a successor model of the highly-regarded SA6 regular with some improvements of tuning and design of its shells. As far as I know, there are two follow-up variants of the SA6, this unit and the slightly re-tuned and a collaboration project with another prominent audio reviewer albeit it's more likely a limited edition, The SA6 Ultra. Like its predecessor, it is still an all-BA (balanced armature) driver set with the same quantity, but undergoes some tweaks and rework on its tuning to make it tonally more superior to surpass the tonal capabilities of its erstwhile elder sister.

As I mentioned a while ago about the same type of transducers that this unit has that was also implemented with the original SA6, The SA6 MK.II has a total of 6 BAs (balanced armature drivers) on each side. These balanced armature drivers are produced by some recognisable names on audio solutions, Knowles and Sonion respectively. The custom Sonion AcuPass Vented Dual Woofer BA (either based on the 31-38 series or on the more common 23 series) handles the low frequency while it uses a dual custom Knowles BAs for midrange and another dual custom high frequency tweeter from Knowles. There's also a small PCB electronic frequency crossover that will give a distinct separation and clarity for each particular frequency, and that said PCB is also connected to the bass toggle switch. It is also noted that the drivers also connect in acoustic tubes in three parts towards the nozzle. The internal wirings that are used to connect between the components are made of high quality, single crystal silver plated copper of high purity.

The shell chassis of DUNU SA6 MK.II are made of high quality German-made, medical-grade and skin-friendly acrylic resin. Then its faceplate panels are made of laminated wood with resin along its contrasting different tones and hues of brown colour that reminds me of a sandstone and amber stone which makes it look very premium and classy with the silver outline print of "6" at the left channel and the with the same silver outline print of the brand "DUNU" on the other channel as it emanates its exquisitely look, sophistication and elegant build yet lightweight. It takes an ergonomic UIEM-style form of its shells and has smooth contours with a stabilising fin for stable insertion on the concha. At the upper part of the shells of SA6 MK.II, there's the bass toggle switches where you can activate to boost some bass in your listening session. DUNU SA6 MK.II has a recessed bi-pin connector which gives a stronger and secured interlocking with its cable and it is also noted that there's a vent hole under it.

The shells of SA6 MK.II are on the medium-sizes and when it comes fitting and comfort, it really secures firmly on my lug holes without any unwanted issues like ear fatigue or discomforts as I've actually been wearing it for almost 12 hours. It also has a good seal and noise isolation as it blocks some external noise from the outside surroundings.

The stock cable of DUNU SA6 MK.II is quite an interesting inclusion that It was marketed as DUNU Hulk Pro Mini. You can purchase it separately either from the DUNU website or other online audio vendors and it is available in two standard pin-types, 0.78mm and MMCX. It's a 4-strand, single crystal copper cable with each wire shielded with aluminium foil and insulated with TPU (Thermoplastic Polyurethane). This cable is also feature's DUNU's proprietary Q-lock Plus modular termination plug system which has an L-shaped, more steady on interlocking between the cable and termination plug and   more quicker of switching plugs which make it even more adaptable depends of interface of multimedia devices like DAPs, smartphones and desktop DAC/amps. It includes 3 types of termination plug; 2.5mm balanced, 3.5mm single-ended and 4.4mm but SA6 MK.II's doesn't have a 2.5mm balanced termination plug.

The product package of DUNU SA6 MK.II is well-executed and its inclusions are properly curated inside the box. It has a medium-size rectangular box for an IEM and its cardboard sleeve has a different tone and accents of orange colour with a Hi-Res certification print at the top-left and model series print at the front part while at the rear, there you can find the basic specification of this product along its company and factory address.

Here are the contents you find inside of the packaging box:

■ a pair of DUNU SA6 MK. II IEMs

■ DUNU Hulk Pro Mini modular cable.

■ 4 pairs of DUNU S&S ear tips of different standard sizes.

■ 3 pairs of DUNU "Candy" ear tips of different standard sizes

■ a pair of memory foam ear tips.

■ 4 pairs of light grey-coloured narrow-bored ear tips of different standard sizes.

■ a 4.4mm balanced output modular termination plug

■ a 6.35mm adapter plug for line-level audio, microphones, electric guitars and loud speakers.

■ a cleaning tool kit.

■ A clam shell-shaped, PU Leather IEM case.

■ some paperworks like Q.C. stub and instruction manual.

With a resistance rating of 24 ohms and 114 dB of sensitivity level, DUNU SA6 MK.II has an excellent scalability on power output. I've tested it on my LG phones, DAPs and USB DAC/Amp dongles. Even a decent amplitude scale level (around 30-40%) will be able to amplify the SA6 MK.II to have a full-range sound with good dynamics.

As for tonal quality, like its quintessential older predecessor, SA6 MK.II retains the balanced-neutral tuning, a slightly elevated bass then a linear and textured midrange and treble. But if the bass boost switch is activated, then it gives a mild U-shaped sonic profile while retaining its neutral tuning.

Here are the sound characteristics in which I observe and listen to within its frequency range spectrum.

LOWS/BASS:

The bass quality of DUNU SA6 MK.II is punchy, articulate and quite vital enough that it delivers an engaging and sufficiently dynamic sounding as I expected from a Sonion BA woofer. It focuses more on mid bass rather than sub bass which I really prefer.

On the sub bass, it has a decent rumble coming from the reverberations of synthesisers, low-toned bass guitar and drum machines from the sub bass-focus audio tracks; either its a synth-pop, classic rock, electronica and old-school hip-hop playlist tracks.

Like I mentioned before, the mid bass is the focal point of SA6 MK.II as it has an adequate texture to give a sufficient note weight on specific instruments like violas, bass kick drums, bass guitar and bass-baritone vocals. Violas have a warm and sensuous sound to give that rich and dark timbre. Bass drum kicks have these resonant and gloomy sounds on them on every attack that reverberates and resounds. While on bass guitar, it has an earthy and sombre sound on every growl and distinct damp sound on either from fretless, slapping and other finger techniques on bass guitar plucksis  Bass-Baritone vocals have enough heft and depth to give that particular wool-like and murky sound from well-known bass-baritones singers like Barry White, Andrew Eldritch and Peter Steele of Type O Negative.

Switching on the bass toggle will give some substantial boost in low range to have a tad warmer sound. The bass register seems to be well-controlled and doesn't muddle up on other frequencies to have a decent clean bass. Take note that this type of bass will not satisfy the ears of bass head maniacs.

MIDRANGE:

As I remember that this was the strongest aspect of the original DUNU SA6's and it seems the SA6 MK.II inherited some of it with some modification to make it more energetic and even more open-sounding. The mids of DUNU SA6 MK.II is textured, clean, detailed and transparent sounding. It gives an accurate timbre on both vocals and instruments alike on how it sounds very natural and captivating to gain your attention on listening to them.

Due to textured lower midrange with enough warmth, the male vocals have an adequate strong, power and guttural quality. Baritone voices have a good rendition and projection on them either the smooth and agile of lyrical baritones like Scott Weiland of Stone Temple Pilots and Lenny Kravitz or more authoritative, warmer and velvety dramatic types like David Bowie and Jimmy Hendrix. Countertenors have these light, penetrating and a bit bright tonal modulation of their falsetto like Thomas Otten and James Bowman on their rendition of Handel's Ombra Mai Fu or modern ones like Yannis Papadopoulos of Beast In Black band. And then on tenor singers, modern ones like Dio, Freddie Mercury (his highest vocal range) and Stevie Wonder have the vocal agility of being dazzling, bright and clear sound on them. On the operatic side of tenor, either on lyrical or spinto, they have these warmer, graceful and brassy characteristics from the likes of Placido Domingo and Luciano Pavarotti.

On female vocals, the manifestation of contraltos like Tracy Chapman, Toni Braxton and Annie Lennox have these smoky, rich and heavily chesty vocals on them. Mezzo-sopranos have smooth, velvety and rounder vocal quality that makes them very hypnotic and luscious to listen with the likes ofc Andrea Corr, Dolores O'Riordan of the Cranberries, Sharon Den Adel of Within Temptation (I love her voice in the track "The Cross") and Enya. On Sopranos, I will divide it into three sub-categories; lyrical, dramatic and coloratura. On the lyrical type, it has silky and sweet characteristics like Alison Krauss and Björk, then on dramatic types like Tarja Turunen, Mariah Carey and Eva Cassidy have these very emotive, rich and silvery sound and last but not the least, the airiness, crystalline and suppleness of coloratura vocals like Diana Damrau and Olga Peretyatko to have bright, energetic and well-extended voices.

As for instruments, they all sound very natural and quite realistic playback on delivering such tonal and timbre accuracy. I start with woodwind instruments, saxophones sound very lively, sonorous and reedy, and the flutes seem to have light, wind-like and ethereal sound. On brass instruments like trombones, trumpet and horns, It does have an eruptive and "dramatic-like" sound on trombones while on the trumpets, they have a substantial, brilliant and penetrating sound and horns have a sustaining sonorous sound at the low register to bright sounding on the upper register. Percussives like toms and snare drums have a penetrating, resonant and rumbling sound on every hit, another percussive instrument that I rarely mentioned was the glockenspiel which has a silvery, striking and shimmering sound. Then celestas the bell-like and ethereal sound to give that "heaven" and royal court ball vibe while the piano has a full range to have warm, lush on the low note to vivid and bright on high note. Strings like acoustic guitars have a buttery to crisper sound on them and more vibrant, visceral and intense on electric guitar riffs especially on rock and metal genre. Then the violins, which are also a string instrument, have a fuller, lively and sparkling sound on them to give a more emotional engagement and solemn atmosphere.

As a midcentric listener like myself, like its original sister, SA6 MK.II delivers such exquisite and well-delineated midrange registers that I can pronounce without hesitation as closer to perfection.

HIGHS/TREBLE:

In my hearing, the treble quality is quite  balanced, with ample brightness and yet very airy which contrasts with the original SA6. The upper midrange seems to have smoothen a bit while retaining its clarity on instruments and female vocals. I don't hear any harshness nor sibilance as it remains  pristine and transparent. There is some hint of elevation on the presence to the brilliance part treble as it gives better details, more air and a tad sense of spaciousness.

Cymbals have a glistening  sound with a good sizzle extension but not in an exaggerated manner. The sounds of Hi-hats were depicted in a life-like sound with a shortened dry and dull sounding to give that distinctive "chick" sound.

SOUNDSTAGE, IMAGING AND OTHER TECHNICALITIES:

The overall sound field dimensions are quite spacious as I perceive them within my head room.  It has an above average to wide when it comes to width, a good and immersive depth from front to the rear if I was at the center and above average on the height reach. In general, If I try to estimate it, I feel that I was in a medium-size theatre hall.

The imaging aptness of DUNU SA6 MK.II is also impressive as it gives me a more engaging experience as if I was in a 3D-like spatial point. I can clearly hear and even pinpoint the exact location of instruments and vocals within my aural sphere. Separation is even impressive as it does have a good spacing between the elements and when it comes to layering, I was able to discern the orderly arrangement on each instrument and vocals with their specific frequency and dynamic tonal layer within the sonic canvas especially on orchestral and jazz tracks.

Resolution capability on DUNU SA6 is also remarkable in how it presents its macro-dynamics and micro-details. Even for all-BA set, it has strong fundamentals on rendering its macro-dynamics and extracting some infos on the subtleties and nuances from audio track data with a sufficiently sharp definition. The tonal profile of this set is still on the balanced and natural side with a miniscule amount of colouration.

The cohesion of its all BA drivers is already expected to an premium balanced armatures along with DUNU's decades of expertise that it sill have a snappier, faster transient and almost zero distortion rating on how it delivers an envelopment of a sound quality.

PEER COMPARISONS:

DUNU SA6 Regular

● This erstwhile archetype has the same transducers set-up, it has a slightly smaller size profile of its shell with different design of its faceplate (if my memory serves right). It also has a bass toggle switch. Its stock cable is actually good and it is also modular but compared to the SA6 MK.II's current stock cable, you will definitely feel the improvement.

● With its tuning that still resonates with me to this day. It is definitely a balance-neutral tuning. It has less emphasis on bass compare to the SA6 MK.II but it is still punchy, a more slightly textured mids, which give the best vocal and instruments detail on its class, and a smoother yet detailed midrange but it is noticeable that it is less sparkling and even less airy compare to DUNU SA6 MK.II.

● Overall, they almost have the same technical performance but DUNU SA6 regular is rather to have an above average /speaker stage width.

AUDIOSENSE AQ7 PRO/INSIGHT:

● Its shell chassis is made of high quality resin and it is quite a bit larger. The drivers of this set consist of 1 dynamic driver and 6 Knowles BA and it uses an MMCX connector as its interlocking mechanism. Both have similar quality and quantity of product packaging and inclusion of accesories but its cable isn't a modular one.

● Both sets have a leaning towards a neutral sound profile but AQ7 PRO is more of a "reference-neutral" sound signature. It has a tighter yet dynamic bass response and more emphasis on midrange to treble. Midrange is also clean and even more transparent compared to MK.II but the latter sounds more natural than dry and analytical AQ7. Treble is a bit brighter on AQ7 PRO and even a tad airier.

■ They both have similar technical performance but AQ7 PRO has a wider soundstage and an even more sharper detail. There are some reports that AQ7 PRO will give some driver flex will give you some minor occlusion effect.

EFFECT AUDIO X ELYSIAN GAEA.

■ This is indeed a TOTL one and almost thrice expensive. The drivers set-up of this unit consists of 1 DD and 4 Sonion BAs. The shell chassis is quite similar in build and construction with SA6 MK.II. It is an Effect Audio product so expect a high quality stock cable but take note it has a proprietary connector.

■ GAEA has a Harmanish-type of tuning, a more U-shaped sound signature. It has more prominent sub bass and at least it has an ample mid bass unlike most Harman-type of tuning. Midrange is a bit recessed yet clean sounding but on the upper mids, it is quite forward on female vocals albeit there are some instances that they are presented a bit too much. Treble seems to be on a brighter side, indeed very detailed but I noticed that it's on the borderline of being sibilant.

■ Technicalities-wise, I consider the GAEA to have an above average rating. It has an above average sound/speaker stage width, depth and height. It has a good separation and layering though its imaging presentation is rather two-dimensional. Resolving on dynamics are on par with SA6 MK.II but GAEA is a bit unnatural in my ears.

As I put my conclusion on assessing the DUNU SA6 MK.II. It seems that DUNU truly proves that once again that it can deliver a product that punches above beyond its price. DUNU SA6 MK.II is just an exceptional IEM earphone that surely outperforms most of its competitors within the midrange category and even to some TOTLs out there with its superb tuning and competent technical capabilities.

But the big question that is floating around the audio enthusiasts sphere right now, does it truly outperforms the original SA6? Yes and No. Yes, just because DUNU improves the quantity of bass, smoothen up some upper mids frequency and even it improves its technical abilities. No as if it adjusting some emphasis on some frequency regions to give a bit colouration on tuning therefore it is less neutral sounding, The tonality of the original SA6 was already impressive and still was my reference point of a balanced-neutral, midcentric tuning in the midrange sets. Overall, DUNU speaks for itself and SA6 MK.II is the testament of it.

Also, please heck out my previous review on other DUNU products:

●DUNU KIMA

​

DUNU SA6 MK.II is now available in HIFIGO, you can check the link below if you are interested to purchase them out.

◆◆HIFIGO (Unaffiliated Link)◆◆

SPECIFICATION:

MODEL: DUNU SA6 MK.II

IMPEDANCE: 24Ω

SENSITIVITY: 114dB

FREQUENCY RESPONSE: 5Hz – 40KHz

CABLE LENGTH: 1.2M

PIN TYPE: 2-PIN CONNECTOR (0.78MM)

PLUG TYPE: 3.5mm

DRIVER UNIT(S): (6) DYNAMIC DRIVER

PROS:

△ Its resin shell chassis have an elegant and classy look on its faceplate.

△ One of the best when it comes to fitting ang comfort due to its lightweight and ergonomic contours of its shells.

△ Quite generous when it comes to quantity of inclusions (That's truly an astonishing treatment of a midrange product to its customers)

△ A switch for bass boost to add more engaging sound on listening session.

△ It includes a high quality, modular cable

△ 4 choices of types of ear tips to choose from.

△ a balanced-neutral tuning that's really suits the hearing preferences to neutral heads or individuals who are quite experienced in high fidelity audio hobby 

△almost DD-like bass response although it is still not a bass quantity of a basshead.

△ Ample textured, clean and transparent midrange

△ Superb vocal performer and very clear instrument presentation.

△ Smooth yet has an ample sparkle and airy treble 

△ Incredibly detailed sounding with good macro-dynamics

△ A noticeable improvement on its technical capabilities compare to the original SA6.

△ The faux leather IEM case is an ornate piece yet it has a good construction quality.

CONS:

▽ Compare to the SA6 Regular, it is a bit coloured when it comes to tonality. (just my nitpicking).

▽ Definitely not for listeners who loves more coloured sound profiles. Sorry bassheads and lean-U shaped (Harman-curve) sound signature lovers, this is not for you then.

Some 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 DUNU nor receive 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 HIFIGO especially to MS. YUMU SONG and MS. LVY YAN. And I also say thanks to NEIL NIÑO CLARK for providing this review unit. I truly appreciate their generosity and trust towards me and other reviewers.