DAC Chip: Realtek ALC5686
PCM 32bit – 384kHz, DNR: -110db, Power: 1 Vrms, USB Type-C Male, 3.5mm SE (Microphone: YES), Metal Chassis & SPC Cable



  • Reference grade, crisp balanced neutral flat timbre, mildly euphonic
  • Vibrant and coherent dynamics, full bodied with smooth presentation
  • Exceedingly well nuanced Micro and Macro details, very transparent
  • Balanced Mids with detailed textures and definition, naturally toned Male/Female vocals
  • Sparkly Treble with crisp smooth decays, great extensions
  • Smooth impactful Mid-Bass, tight, fast with crisp decays
  • Sub-Bass with tingling seismic response, natural decays.
  • Crisp and vivid guitars, piano, percussions (chimes, bells) and drums and taps
  • Amazing holographic spatial imaging with sharp precise placement/layers
  • Amazing speed and dexterity on complex passages and transients
  • Super clean background, zero floor noises
  • Super clean layers and well-defined separation lines
  • Drives Magnetic Planars and BA at 80/100 volume, great fidelity
  • Excellent synergy with many type of IEMs/HPs
  • Forgiving on Lo-Fi and lower quality sources
  • Low battery drain on the host
  • Does not heat up easily


  • Driving power for great fidelity maxed out below 100Ω and with no less than 90db sensitivity.
  • A bit flatter sounding sometimes compared to the top 3 performers
  • No volume adjuster
  • Amazon only item, not available elsewhere
  • May suffer from QC issues, if you are lucky you get a great copy, with $9 there has to be a compromise since this is not a bespoke handmade unit, it is an assembly line product, probably with near zero QC (just like tons of other ultra budget Dongles)

DAC Chip Update

There’s 2 versions of ZOOAUX, the one I reviewed here is the older ALC5686 variant, the current one offered by Amazon is CX21988 variant which is equally similar in SQ performance and the review of that unit is here with Yannick’s Reviews

29 July 2021. It came to my attention that Amazon ZOOAUX recently advertised their PCM spec as 24bit-96kHz. This is vastly different from the unit that I have tested (32bit-384kHz) . While the tuning may still be identical but this could also mean they may sound slightly different. Amazon’s Xumee is still ALC5686 (same as the old ZOOAUX).


ZOOAUX. From the first listen I already knew this one is a top ranking performer. Sonic quality from this ZOOAUX is illegally amazing.

ZOOAUX passed the FOSTEX T40RP MK3 91db Magnetic Planar brutal test gracefully. It does need the volume to be cranked all the way to 80-90/100. But once desired loudness has been set, the output is wholesome and vibrant. No indication of timbre coherence being sacrificed despite being maxed out on the load to drive that beast. No hint of jitters or edgy micro distortion even playing Hans Zimmer “Mombasa” and Massive Attack “Angel”. Speed was stellar with deftly handled transients and great resistances to compression and congestion. Admittedly Ovidius B1, Hidizs S9, S9 Pro and hiliDAC Audirect BEAM 2S sounds meatier with the T40RP, due to their sheer higher amp stage output which ZOOAUX does not have. But this does not mean ZOOAUX is inferior, it is just flat neutral with proper dynamics and I am completely satisfied with that. Not forgetting the stellar imaging and spatial staging which is undoubtedly among the best I have heard so far, outclassed only by THX Onyx in sheer width (ZOOAUX still sharper vs Onyx)

With the highly sensitive 122db Aria, ZOOAUX was nothing short of being Amazing. First thing that greeted me was the MASSIVE soundstage that does not sacrifice imaging and spatial projection. Despite being a soft U curve IEM, Aria surprisingly sounded rich in the Mids with Diana Krall voice lush and natural. Bass responses super tight and fast, Treble as smooth as it can be. Similarly with HZSOUND Heart Mirror, the output is sparkly brighter and Bass responses tighter and fast. Dynamics with great coherence and stability. Both Aria and Heart Mirror loving the synergy with ZOOAUX. Aria remained warmer, Heart Mirror sparkier.

Etymotic ER4SR & VE Asura 2.0. I have grouped ER4SR and Asura together because the output that I have heard from both were similar in many ways. While ER4SR remained true flat neutral and Asura slightly Mids focused, the rest of the spectrum are closely matched. Of course ER4SR still being the faster one with that BA speed and resolution. Tonality wise they are similar sounding with ZOOAUX – very well balanced and wholesome. These two needed some beef to sound full, ZOOAUX has that meat. ZOOAUX yet again exhibited great synergy to drive both with visceral authority and guile. As a DF Neutral fanatic, I am loving this output so very much. Admittedly I get warmer and more musical results from Ovidius B1 and VE Odyssey HD, but the smoothness and polished presentation is there with ZOOAUX.

Shure KSE1500 Electrostatics. Paired with ZOOAUX as an AUX feed (pun intended), fidelity level goes even higher with this TOTL IEM. ZOOAUX clean and pristine output merged well with KSE1500 zero distortion characteristics. Being ultra-resolving, KSE1500 would have revealed any imperfections the source has, it can be quite merciless but ZOOAUX remained clean sounding. Dynamic range audibly broader with deep extensions on all frequencies that reveal everything the source has to offer. The beauty or ugliness of the feed all laid bare for the ear to savor. Micro details presented with succinct details yet it remained realistic. There’s no artificial element to the sound. It is as natural sounding as it can be. Audio realism as I called it. In contrast, VE Odyssey HD and hiliDAC Audirect BEAM 2S (the other 2 favorites serving AUX for my KSE1500) offered warm neutral timbre, with focus on lush and comforting smoothness. With ZOOAUX my KSE1500 sounded polished crisp. It is great to have options to swap Dongles to suit my moods.

Ultra-Critical Tests #donglemadness Top Performers

IEM: ETYMOTIC ER4SR (98db, 45Ω )
Source: Windows 10, Native Windows USB Drivers
Ovidius B1: (Single Ended 3.5mm) Adaptive Gain
L&P W2: (Balanced 4.4mm) High Gain
ZOOAUX: (Single Ended 3.5mm) Fixed Gain
EQ: Always Off

ZOOAUX vs L&P W2 vs Ovidius B1 (6 passes for each Dongles)


  • W2 (Vol 52/100), ZOOAUX (Vol 32/100), B1 (Vol 14/100)
  • Micro Details W2 equal ZOOAUX. B1 slightly more pronounced
  • Crisper Piano tone on B1, W2 and ZOOAUX equal
  • Shorter decays on ZOOAUX, Slightly longer on W2 and B1
  • Intimate Mids on ZOOAUX & B1, W2 slightly spaced back
  • Overall timbre: W2 & B1 slightly warmer, ZOOAUX neutral
  • Timbre coherence equal on all three
  • Background on silent passages equal for all three


  • W2 (Vol 56/100), ZOOAUX (Vol 32/100), B1 (Vol 14/100)
  • Overall timbre W2 and B1 equal, ZOOAUX very slightly brighter
  • W2 Mids spaced back 1 step, B1 & ZOOAUX equally intimate
  • Timbre coherence equal on all three
  • Everything else performed equally (timbre, transparency, details, speed, soundstage, imaging & extensions)

In addition to my own tests, I decided to extend it further and asked the help of two members from ChiFi Audio Reviews FB group. Edmund Chan and Syazwan. Edmund being a seasoned Audiophile highly respected in the Malaysian Audio scene, He is a crew of AudioMonsta Malaysia. Syazwan on the other hand, is a freshly made Audiophile and I opted to ask him to share his impressions as well. This way I am able to gauge the perspective from both end of the spectrum = seasoned and fresh perspective.

ZOOAUX must be an accidental freak. I don’t think the manufacturer of this Dongle even realized what they have created. To date I have tested over 20 units of Dongles from Amazon and 98% of them are nowhere near being as great as this one. The biggest caveat perhaps the possible risk of getting a bad copy among the batches. These are assembly line products and does not go through bespoke QC as how high end devices would be subjected to. So it’s a Russian Roulette Dongle for sure.


Best Pairing: Flexible for anything less demanding under 100Ω

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