The HiBy R4 proves that you don’t need to spend thousands of dollars on a digital audio player to get exceptional sound. This $250 USD device outperforms many other DAPs I’ve tested with its powerful parametric EQ system and technical capabilities. Android 12 combined with audiophile-grade features makes the R4 an attractive choice for music lovers who want value. Is this DAP too good to be true though? Let’s find out.

---

---

• HiBy R4 with pre-applied screen protector
• USB-C to USB-C cable
• TPU case
• Extra screen protector
• Documentation

---

The HiBy R4’s striking cyberpunk aesthetic is seen immediately during the unboxing. Bold geometric lines and industrial design elements give this device an unmistakable presence. The audio player stands apart from typical minimalist designs and features an angular chassis that seems pulled straight from a cyberpunk anime.

The R4 showcases a futuristic vision through its offset hatch patterns and mechanical-inspired elements. I love how the design team added hidden LED light strips in the rear glass panel that creates a subtle sci-fi atmosphere. There’s also an LED strip on the front of the R4 to indicate playback sample rate, as well as charging. Black, orange, green, and silver versions are available, and each color brings its own unique personality while staying true to the cyberpunk theme. I opted for the black version.

My hands-on testing revealed surprisingly solid construction quality for a $250 device. The R4 features:

• Full aluminum frame construction
• Scratch-resistant metal surfaces
• Durable plastic buttons

The frame remains rigid without any flexing or creaking under pressure during durability tests. The angular design creates some practical challenges though. Sharp corners make extended handling uncomfortable, even with the included TPU case installed. A lanyard loop is present on the top left of the R4, and if you pre-ordered or ordered the R4 within a certain time frame a lanyard was included as a bonus. It’s not something that I will be using, but it is there for those who want it, and it also adds a bit of uniqueness and fun to the look of the DAP.

The R4 features a 4.7-inch Sharp LCD display that shows crisp visuals at 720×1280 resolution. The screen looks bright and details are crisp as I browse through music libraries and adjust playback settings. HiBy thoughtfully includes a screen protector, which is pre-applied at the factory.

The device has a well-thought-out layout. The volume buttons and MicroSD card slot sit on the left edge, and power and playback controls are on the right side. A customizable function switch on top, and by default, it is set to lock the buttons when enabled. This is to stop the buttons from getting pressed accidentally in your pocket or when handling the device. This is a needed feature as I found it incredibly easy to accidentally press the buttons, especially when picking the R4 up from a desk or table. The buttons provide inconsistent tactile feedback, and on numerous occasions, I accidentally changed tracks despite feeling like I didn’t press the button all the way or simply grazed it with my thumb. They could use more rigidity or resistance to compensate for that.

I also wish the buttons were textured differently so you could quickly tell them apart by feel. Only the power button has a different size and texture.

You’ll find both 3.5mm and 4.4mm headphone outputs at the bottom, next to the USB-C port that handles charging and data transfer.

The R4 measures 129.6 x 68.3 x 18.5mm, making it thicker than most smartphones. Still, it works fine as a portable device. Its 231g weight feels solid and premium in hand, easily convincing you that it is a more expensive device.

---

HiBy R4’s software experience matches its hardware capabilities well. The device combines easy accessibility with advanced features that impressed me throughout my usage.

Storage

The R4 supports microSD cards up to 2TB in size. I did have issues with my SanDisk 1TB and 512GB Extreme cards though, as the R4 sometimes had issues seeing the cards after they were inserted, as well as getting hung up when scanned by the HiBy Music app. As well, even after it looked as if all was good, tracks would skip or crackle. Reformatting the cards on my PC as exFAT instead of FAT32 seemed to resolve all the issues for me though, so YMMV.

The 32GB of internal storage is not very much, especially once you start installing apps, so I would recommend using a microSD card regardless. I detected no sound difference between the internal storage and the microSD cards I have.

Android 12 OS

The R4 runs Open Android 12 and delivers impressive performance despite its modest 3GB RAM setup. HiBy chose a minimalist approach to their Android skin that stays mostly stock. The interface is very responsive, as are app launches and installations. It feels on par with modern smartphones in terms of fluidity, and I never felt like I was waiting on the R4 for anything.

You won’t be getting the latest OS updates with the R4 as you have to wait for HiBy to build and package them, and they haven’t indicated their level of support for their Android-based DAPs. It is less of an issue for digital audio players though since they usually aren’t internet-connected all the time, with most playback being intended for offline use. Apps can be installed through the Google Play Store, or you can sideload them and manually install APK files.

HiBy apps are pre-installed, as well as the Via web browser which is known for being fast and lightweight. I did have some issues with this though when signing into various apps that use it as a default browser to authenticate credentials. Some apps, such as Sony Sound Connect, refused to work with Via and I was forced to install Chrome. After that, Sony Sound Connect was able to load the proper web page for authentication.

HiBy Audio Settings and Apps

HiBy OS is HiBy’s implementation of systemwide bit perfect audio, meaning that it bypasses Android’s stock audio stream with a custom developed one that doesn’t resample bit depth and sample rate. Instead, you get bit perfect audio regardless of which audio app you are using. Contrast this to Sony’s Android implementation as I’ve discussed in previous reviews, which only gives the Sony Music Player access to bit perfect playback. Ironic I suppose that a $250 DAP can do something the $1500 Sony Walkman NW-WM1AM2 cannot.

Along with a bit perfect audio stream, HiBy also includes systemwide audio plugins, as well as a 10-band PEQ (parametric equalizer). Currently, there are 5 plugins available and can do things such as set a fixed sample rate, increase or decrease the sound field, or adjust dynamics such as the bass and treble. The PEQ works well, and you can save, export, and import EQ files.

MSEB is an audio feature that allows you to tune various audio properties. You can make the audio sound warmer or cooler, increase or decrease bass extension, and even manipulate note thickness. There are a lot of options to choose from depending on the sound you are going for, and HiBy includes four different presets to give you a taste of what’s capable.

The HiBy R4 is pre-installed with HiBy Music Professional Edition, which as far as I can tell, the only difference between it and the version available on the Play Store is the ability to play MQA files (which is a paid add-on for the regular version of the app). The HiBy Music app works very well as it’s fast, has a good level of customization, and even has its own built-in GEQ, PEQ, and MSEB sections, as well as the same Plugins that are available in the systemwide audio settings. I have two gripes with the app though. The first is the lack of any sorting features for albums when using either the Artist or Album Artist fields (I always prefer to sort albums by year, HiBy Music only sorts albums alphabetically). Second is how the Album Artist field sometimes shows empty albums from a similarly named artist. For example, albums from “Mark Lanegan Band” show up when looking at “Mark Lanegan”, despite the artist and album artist name metadata being filled out correctly, and it seems to only be a problem with the HiBy Music app as using other music playback apps don’t show this issue.

Lastly, there is the HiByCast Server app. This allows you to use the HiByCast app on another device to remotely control the R4. It’s essentially a screen mirroring and control type of app, which is intended to be used if your R4 is docked and part of your media center. It’s a cool feature that probably won’t get used by most people, but will be invaluable to those that do have a use case for it.

Streaming app support

R4 stands out from many other Chinese DAPs because it comes with Google Play Store pre-installed. Popular streaming services like TIDAL, Qobuz, Spotify, and Apple Music work flawlessly with bit-perfect output and systemwide PEQ. The HiBy Music app features streaming support built-in for Qobuz and Tidal, but standalone apps offer better functionality. The R4’s ability to switch between local and streaming playback works really well due to how performant the overall device is.

Device and Mode Settings

The R4 has several “Working Mode” settings that enable different features when selected. Pure Android mode locks the HiBy Music app open so that you can’t access any other installed apps, which instead allows you to focus on just the music player. USB DAC Mode does exactly what it says, enables the USB DAC functionality, and gives you a display where you can see the sampling rate of the currently playing audio. Bluetooth Receiving Mode allows you to turn the R4 into a Bluetooth DAC/Amp and receive audio from other sources.

I tested all of these modes and did not encounter any issues with them, and actually, I’m impressed with how well HiBy implemented them.

The Display settings section of the Settings app contains the options to enable/disable the front and back LED lighting features, as well as various other options.

Bluetooth and WiFi capabilities

The R4’s wireless connectivity proved strong during my tests. HiBy’s Bluetooth 5.0 supports an impressive range of codecs, SBC, AAC, aptX, aptX HD, LDAC, and HiBy’s proprietary UAT. I found the two-way functionality to work well, allowing me to pair the R4 with my PC or laptop to be used as a Bluetooth DAC/Amp. I had no issues connecting any of the wireless headphones I use, including the Sonos Ace, Sony WH-1000XM5, and Sennheiser Momentum True Wireless 4 earbuds. The LDAC and aptX HD codecs sounded and performed exactly as I expected them to, and the range was in line with other DAPs and smartphones I’ve used.

The dual-band WiFi (2.4GHz and 5GHz) works reliably with streaming services. My connection stayed stable even in tougher spots in my apartment. Using the 5GHz band of my Ubiquiti U6 Pro access point I noticed a connection speed of 433 mbps, falling in line with most other digital audio players. The Sony Walkman DAPs, which despite connecting at 433mbps, seemed to be capped or bottlenecked somewhere as downloads and file transfers over WiFi are painfully slow, usually under 10MB/s. With the R4 I was hitting 30-35MB/s almost all of the time, which means less waiting and more listening time.

Battery

HiBy states the R4 lasts up to 11 hours when using the 3.5mm connection. In my own tests of using low gain, WiFi off, Bluetooth off, and the volume level set at 26, I managed just over 12 hours of playback time. This is a solid showing and I’m happy to see no marketing deception here. Charging from a completely dead battery takes just over 2 hours, and the R4 can even be charged when powered off. Standby time is simply superb as well. HiBY states it the R4 can last 675 hours in standby/idle mode. I didn’t test this explicitly, but I can confirm that the R4 will only lose a percent or two over 24 hours of no usage.

---

The HiBy R4’s sonic capabilities are extremely solid for a device of this price. My tests with IEMs, wireless earbuds, and wired and wireless headphones of all types proved that this player delivers performance beyond its price point. Let’s first look at the technical components.

Quad DAC setup

The R4 comes with a quad ES9018C2M DAC configuration. This high-performance setup produces crystal-clear and detailed sound reproduction. The four DAC chips work together seamlessly to deliver exceptional resolution with expanded dynamic range with superior signal-to-noise ratio performance, as well as better stereo channel separation. Decoding support includes MQA, PCM up to 32-but/768KHz, and DSD256.

Class A amplification

The R4’s Class A amplification system packs four OPA1652 and two OPA1612 operational amplifiers that deliver remarkable power output. It’s incredibly rare for a portable device like a DAP, let alone one at this price point, to have a Class A amp (they’re very power-hungry). The Class A design makes the device run a bit warm, but the superior sound quality makes this trade-off worthwhile.

Sound Profile

The HiBy R4 stands out with its neutral sound signature. Many players color the sound, but the R4 stays clear and transparent. This quality shines in the midrange where vocals and instruments retain their natural character without artificial sweetening. Resolution is also very good here, allowing you to hear subtle nuances in vocal performances and acoustic instruments that other players might miss or push back. The bass stays tight and controlled, and the treble extends smoothly without any harshness or fatigue. The player handles dynamic passages with exceptional clarity, even during complex orchestral pieces.

The R4 creates a well-defined spatial image that separates instruments beautifully. The 4.4mm balanced output shows improved dynamics and separation compared to the single-ended connection, but both outputs keep the same neutral tonality.

This player knows how to drive headphones of all types. Most IEMs don’t need high gain, but there’s plenty of headroom for demanding full-size headphones. I never had to use more than medium gain for any of the headphones I have. I don’t think power will be an issue for most people here.

---

The HiBy R4 shows you don’t just need to pay premium prices for exceptional audio performance. This digital audio player packs a powerful quad DAC setup with detailed sound customization options and solid build quality. You’ll find features here that usually come with much pricier devices. Android 12 works alongside audiophile-grade components to create a versatile player that shines in both technical ability and everyday use.

The R4’s true strengths become clear with daily use. Its reliable battery life, excellent feature set, and strong app support make perfect sense for serious music lovers. The systemwide bit perfect audio and PEQ are really the stars here. HiBy’s steadfast dedication to performance and user experience is clearly evident. The R4 performs consistently well, whether it powers demanding headphones through its balanced output or works as a portable USB DAC. You’d never guess its modest price tag from its performance. I still hate the buttons though.

---

I’m not always able to cover all the details of a product, both hardware and software, in our reviews. If you have any specific questions you’d like answered about this product please feel free to leave a comment or contact me directly.

Be sure to check out our excellent Buyer’s Guides, as well as our other Reviews.