HiBy R3 II review —— head-fi

Pros: Size
Good detail retrieval
No significant compromise in soundstage
Cons: Audio latency over AAC connection
Album art compatibility issue
One of my biggest disappointments when it comes to to IEM setup is the lacklustre sonic quality of smaller and more budget-friendly music players comparing to their full-sized counterparts, especially when it comes to staging, detail, and dynamic. Of course, we cannot expect tiny boxes with little battery and little space for cooling to match the larger and more sophisticated ones. But I don’t think it is unreasonable to expect more when driving IEMs, especially when even bluetooth earhooks are getting way better. Today, I take a look at HiBy R3 Gen II to answer the burning question: can micro DAP be good?


  • In this review, I use the term “source” to denote a DAC+amp combo for brevity and convenience.
  • Sources do not make sounds. Therefore, when I say sources “sound” a certain way, I talk about the change they make to my IEMs and earphones.
  • I want my music to be crisp, clear, well-separated and form a 3D soundstage around my head. Sources that intensify those characteristics of my IEMs are considered “better”.
  • The unit used for this review was a preproduction sample provided by HiBy (Thank you!). The unit is retailed for $179 and can be found on HiBy official store (non-affiliated link)


  • Operating system: HiBy OS (Linux-based)
  • Decoding chip: 2xES9219C
  • Screen: 3.2-inch touch-sensitive (320x480)
  • Built-in storage capacity: N/A
  • Expansion interface: microSD, upto 2TB
  • Wireless network: Wi-Fi 2.4GHz, Bluetooth 5.1 (UAT, LDAC, aptX (transmit), AAC, SBC)
  • Terminal: 4.4mm balance (PO / LO), 3.5mm unbalanced (PO / LO)
  • Nominal output power: 280mW ( Balanced), 70mW (unbalanced)
  • Continuous playback time: about 15 hours (2000mAh)

Non-sound Aspects​

Build quality:
  • Aluminium frame, sandwiched by glass panels.
  • Screen protectors pre-applied from factory.
  • Buttons have no wiggle. Pressing actions are firm and crisp.
  • Volume wheel have decent snap between notches. It can be operated with one hand. At the same time, I have not had any case of volume adjusting itself in my pocket.
  • Small enough to fit in my palm.
  • Thin and light enough to slip into jacket’s pocket or trouser pocket without adding bulk.
  • The included plastic case is quite difficult to put on or remove.
  • A new version of HiBy OS.
  • You can filter your music by album artists now.
  • R3II can stream Tidal and Qobuz in addition to playing local files in SD card.
  • Scrolling is smooth and responsive.
  • Building music database from SD card does not take long (less than 1 minute for 10 GB of music).
  • 10-band EQ and MSEB are still available for EQ needs
  • Wifi is reliable enough to stream TIDAL at master quality.
  • I couldn’t connect to enterprise Wifi networks (the ones with username and password). No problem connecting to iPhone hotspot and home Wifi.
  • R3 II can send audio to bluetooth devices.
  • R3 II can receive audio via bluetooth. I have very bad delay with AAC via iPhone, meaning I cannot use R3 II to watch YouTube videos. The audio quality is as expected from AAC. I didn’t try LDAC. In my experience, HiBy OS devices tend to work better with LDAC than AAC.
  • Strong battery life when playing local music. I consistently have two to three days of listening with around 4 to 5 hours a day.
  • Battery drops noticeably faster when streaming TIDAL.
Software issues in the preproduction firmware (HiBy might have fixed these problems in the production version):
  • The screen sometimes hangs after waking the device from sleep. Fixable by sleeping and waking the device again.
  • Clicking on my playlist in Tidal crashed the OS.
  • Album arts must be baseline JPG. Many of my album arts do not show because they are in the progressive JPG format.

Sound Performance​

Neutral tonality: R3II does not add warmth or thickness to the midrange. It does not add the usual glare and brightness that some ESS-based dongles tend to have.

Light note weight: The midbass seems more quiet with R3II in direct comparison against most dongles and DAPs in my collection. The subbass is still presented properly, so R3II is still dynamic and impactful when the music calls for, but it is not weighty.

Detailed: detail retrieval across the frequency is strong. To put in context, the detail of R3II is quite close to Chord Mojo2 and DX300.

Soundstage: when playing spacious orchestral recordings with good IEM, the gap between R3II and the previous generation and some dongles are quite clear. R3II can present proper space between instruments and the listeners, as well as between the instruments themselves. There is also a strong separation between foreground and background. Simply put, whilst R3II does not match a desktop setup or a TOTL DAP like DX300, it does not limit the staging performance of my good IEMs to an unacceptable level that I usually experience with dongles and micro DAPs.

Handling Low-impedance, low-sensitivity IEM (E5000): R3II did a decent job. However, E5000 sounds noticeably small and more congested with R3II comparing to DX300.

Handling high-impedance transducers (TGXear Serratus, 300ohm): The gap between R3II and DX300 was smaller than the E5000 pairing. It seems that R3II has problem with current delivery rather than voltage.


I admit: I didn’t have much expectation when I heard about R3II. However, the device quickly won me over with the portability and sound quality. No, this tiny box does not offer the sound quality that makes my DX300 redundant. However, it does not hinder the soundstage performance of my IEMs significantly whilst being much more compact and pocketable. And that’s what a micro DAP should do.

Absolute Sonic Performance: 3/5 - Good.

Bias score: 4/5 - I am happy to add this device to my rotation.

  • Size
  • Price
  • Battery
  • Good detail retrieval
  • No significant compromise in soundstage
  • Audio latency over AAC connection
  • Album art compatibility issue

HiBy R3 II Review - Affordable HiFi Digital Music Player 1

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