Note that this is a discontinued product. You may want to visit the brand's page here to browse their newer products.
What reviewers think
Magazine reviewers and YouTubers have tried this product—so we've summarized their strongest opinions below.
Product Strengths
- Beautiful build with a solid and high-quality feel
- Lovely smooth volume control
- Very noticeable bass depth goes down deep, providing a rich, deep bass sound
- Refined, smoother, warmer, and more organic/analog sound
- Lightweight, making it easy to carry around
Product Considerations
- The BU1 tends to err on the bass-heavy side, which may not be suitable for bass-heavy headphones
- Easy-to-throw gain switch can accidentally damage sensitive IEMs
- USB micro is not as durable as USB-C
- Lacks Bluetooth connectivity and balanced output
Takeaway: The BU1 is a well-built and lightweight DAC/amp that significantly improves sound quality, especially in bass depth, making music sound richer and more refined. It could be worth buying if one wants to enhance their smartphone or computer audio experience with a warmer and more analog sound.
Compared to their other products
We think it's helpful to understand how this product fits into the brand's full lineup (below). To learn more about these products, visit the brand's page.
BU1-Portable-DAC-with-Headphone-Amplifier
- Positioning: Entry-level design focused on portability and affordability.
- Description: Offers a compact DAC and headphone amplifier suited for on-the-go audio setups and small room use, with a straightforward design that meets basic connectivity needs. Compared to other models, it has fewer advanced controls and processing options, making it ideal for users with a limited budget and simple functionality requirements.
Yuki-USB-DAC-with-Headphone-Amp
- Positioning: Budget-friendly desktop solution designed for streamlined USB audio performance.
- Description: Features a clear USB input interface and precise DAC circuitry that provide improved sound clarity for desktop listening. Compared to the portable BU1 and more feature-rich models, it addresses basic needs at a modest cost while offering reliable performance for everyday use.
X1s-GT-X1s-GT-BT-DAC-with-Headphone-Amp
- Positioning: Mid-range option offering a blend of wired and wireless connectivity for versatile setups.
- Description: Integrates both Bluetooth and digital inputs in a robust DAC/amp package that supports varied audio sources, making it adaptable for home or portable applications. Compared to the entry-level designs, it provides better build quality and added connectivity without reaching premium price levels.
X8-XVIII-X8-XVIII-BT-Magic-DAC
- Positioning: Advanced model featuring a unique Bluetooth transmission system for enhanced digital audio.
- Description: Introduces a proprietary BT Magic feature that improves wireless connectivity and digital conversion quality, making it a notable upgrade in performance for modern audio setups. Compared to lower-priced models, it delivers superior digital-to-analog conversion and connectivity features while still being positioned below the top-tier S9c Pro.
S9c-Pro-DAC-with-Headphone-Amp-with-AL3-XLR-Balanced-Male-to-Female-3-Pin-Audio-Cable-1-Pair
- Positioning: Premium high-end solution optimized for balanced outputs and precise audio reproduction.
- Description: Uses advanced DAC circuits and balanced amplifier outputs that provide superior audio detail and technical refinement. Compared to every other model in the lineup, it offers more versatile connectivity options and a higher standard of build quality.
Read the reviews

BU1
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Our take on the brand
What if you spend a bit more?

Our Summary
Product Strengths
- Improved battery management offering faster charging rates and better efficiency than its predecessor
- Features a new USB-C data input for greater flexibility alongside other inputs
- Offers the world's first lossless DSP for tone adjustments without degrading sound quality, providing customization options
- Excellent resolution and dynamics with a large soundstage and extreme detail
Product Considerations
- The Mojo 2 can get warm when in a pocket for a period of time
- Complicated menu navigation with color-coded buttons that may require the manual
- Still uses Micro-USB for charging, which some find outdated
Takeaway: The Chord Mojo 2 is an exceptional DAC/headphone amplifier for those seeking high-resolution audio and customized sound in a portable format that is easy to move. Its sonic accuracy, detailed soundstage, and improved features provide a versatile and enjoyable listening experience, making it a worthwhile consideration for audio enthusiasts.
Video review
Our take on the brand

Our Summary
Product Strengths
- Versatile connectivity with both wireless (Bluetooth 5.1 with various codecs) and wired options (USB, S/PDIF, analog inputs) makes it suitable for various setups—from desktop to portable usage
- Eloquent, informative, and entertaining sound quality, able to produce clear, non-artificial sound across different headphones
- Features such as XBass II and XSpace provide additional sound shaping options for the user to customize the sound to their liking
- The aluminum build provides a robust and premium feel, with a design that's described as sleek and comfortable to handle
Product Considerations
- The user interface is not very intuitive
- Decent headphones are needed to reveal its quality
- The OLED screen can be difficult to read
- Battery life is around six to eight hours
Comparisons (according to reviewers)
- Compared to the hip-dac2, the Gryphon offers better sound quality, more features, and flexibility
- Compared to the iFi GO bar, the Gryphon is bigger and has a built-in battery, and the GO bar is much smaller and draws power from the source device
- Compared to the iDSD Diablo, the Diablo has more power for very demanding headphones, Gryphon has more functions
- Compared to the Zen DAC, the xDSD Gryphon has a more sophisticated and detailed sound
Takeaway: The iFi xDSD Gryphon is a portable and versatile device delivering high-quality sound with extensive features that cater to audiophiles. Its ability to improve sound quality from various sources and its robust build make it a worthwhile investment for music lovers on the go.
Video review
Our take on the brand
What else competes at this price?

Our Summary
Product Strengths
- Detailed and expansive presentation, offering a sonic upgrade to phones, especially when portability is a priority
- Versatile, with both wired and wireless connectivity options, including balanced and unbalanced headphone outputs
- Impressively small size and lightweight design, making it pocket-friendly and convenient for on-the-go use
- Sound quality is generally linear, with fast and accurate bass, flat and clean mids, and a detailed treble that is not harsh
- XBass and XSpace features offer customized listening experiences
- Build quality and aesthetics are generally well-received, with its design standing out from other devices
- ChronoDial volume knob is particularly praised for its tactile feel and functionality
Product Considerations
- Black rubberized plastic casing can feel a bit flimsy to some users
- Some reviewers noted hiss with sensitive IEMs, especially on the balanced output
- Battery life estimation can be unreliable
- No dedicated app for the device, limiting EQ and DSP options
- Lacks a clip, making it less convenient for truly portable use
Comparisons (according to reviewers)
- Compared to the Audiolab M-DAC Nano, the Go Blu offers a wider soundstage, better separation, and dynamic sensitivity, though the M-DAC Nano is fractionally punchier in the bass
- Compared to the AudioQuest DragonFly Cobalt, the Go Blu is a wireless proposition, unlike the DragonFly Cobalt, which is a USB plug-in DAC
- Compared to the FiiO Q3, the iFi GO blu highs are a bit too brilliant, but everything else sounded quite impressive
- Compared to the NuPrime Hi-mDAC, the iFi GO Blu mids sound a lot like it, even if voices are slightly less natural
- Compared to the Hidizs S9 Pro and Aune BU2, the GO Blu provides a relaxed sound and has better build and functionality compared to the Hidizs S9 Pro, but is better when using bluetooth compared to Aune BU2, however when competing on wired terms, the Aune is clearer
Takeaway: The iFi GO blu is a tiny but mighty device that delivers impressive sound and versatility—improving the wireless music experience. It is easy to use and has some cool features, making it a good pick for anyone looking for a portable upgrade for their headphones.
Video review
Our take on the brand

Our Summary
Product Strengths
- Versatile as both a headphone amplifier and preamplifier
- Features bass, mid, and treble tone controls for customized sound
- Offers a loudness button to enhance bass and treble at low volumes
- Has a built-in battery for transportable use
- Powerful output to drive various headphones
Product Considerations
- Not ideal for highly sensitive IEMs due to potential hissing at higher volumes
- Size and weight may limit practical portability
- No DAC, relies on external DAC
- Tone controls reduce power output
- The potentiometer is a little bit on the cheaper side, there is a slight bit of channel imbalance when at very low volume
Takeaway: The Fosi Audio SK01 is a versatile and powerful headphone amplifier with tone controls, making it easy to customize audio and drive various headphones, and its battery and preamp functionality are perfect for those seeking a transportable and flexible audio solution
Video review
Our take on the brand

Our Summary
Product Strengths
- Phenomenal sound quality.
- Very usable and enjoyable interaction due to a physical volume knob.
- Plenty of power for almost everything and can drive just about anything.
- Versatile; it can be used as a desktop all-in-one, a Bluetooth portable DAC/amp, a portable amplifier, and even a DAC for speakers.
Product Considerations
- Susceptible to EMI noises, which can be a deal breaker; static noises, pops, and crackle sounds can occur when a phone is placed directly on top of it.
- Not a completely balanced architecture; the 3.5mm & 4.4mm headphone outputs sound the same.
- Charging port may not indicate charging on anything higher than an 18W charging block, and some chargers may not work.
Comparisons (according to reviewers)
- Vs FIIO BTR-7: Sounds more refined and has more detail and resolution.
- Vs SMSL C200: The C200 sounds significantly warmer with a fuller, juicier bass line and a little bit more airy, while the G5 is more focused on clean and clear edges, tidy, well-focused—and clean.
- Vs SMSL M500 MK2: The M500 MK2 sounds overall better with dynamics at the same level as the G5 and fuller, warmer tonality—and a bigger, more spacious soundstage.
- Vs Moondrop Moonriver 2: The treble is more refined, better details up top, and a sharp edge without being overboard like the Moonriver 2 can.
Takeaway: The G5 is a well-built and versatile portable DAC/amp with a neutral, clean, and dynamic sound. It is great for those looking for an all-in-one solution that can drive almost any headphone or IEM.
Video review
Our take on the brand

Our Summary
Product Strengths
- Excellent sound quality with great technical capabilities
- Powerful output, sufficient to drive many full-sized headphones adequately
- Sturdy, solid metal build, described as being built like a tank
- Offers both balanced (4.4mm) and unbalanced (3.5mm) headphone outputs
- Compatible with Android, iOS, Windows, and Mac
Product Considerations
- Heavier than similar dongle DAC/amps
- Sharp edges can be uncomfortable and may scratch other devices
- Design is considered industrial and not particularly stylish
- Cable's quality is perceived as low
- Volume control affects the source volume instead of having independent control
Comparisons (according to reviewers)
- Vs. FIIO FC3: Has a warmer, more engaging sound, while the FC3 is more neutral and analytical with better detail and resolution
- Vs. Shanling UA3: Wins in macrodynamics making the music more fun, while the UA3 sounds more refined with a slightly more spacious stage
Takeaway: The DS1 is a compact and robust dongle DAC that delivers impressive sound quality and sufficient power for most IEMs and many headphones. It is worth checking out for anyone wanting a solid-sounding and well-built DAC/amp for on the go.
Video review
Our take on the brand

Our Summary
Product Strengths
- Impressive power, especially from the 4.4mm balanced output (510mW at 32 ohms) for a budget-friendly device, capable of driving many headphones—including some planars
- Priced affordably, making it a good value for the performance it offers
- Simple, robust design with an aluminum alloy housing that feels light yet durable
- Delivers a detailed and clean sound
- Compatible with Android, iOS, Mac, and Windows devices
Product Considerations
- The 3.5mm output has significantly less power than the 4.4mm balanced output
- Some reviewers found the sound presentation to be slightly thin or clinical, lacking some weight or fullness in the bass and lower mids
- Lacks advanced features like gain settings, EQ, or filters, physical volume buttons only control volume levels
- Some reviewers prefer other DACs under $100 for their more natural sound
- The volume control is not independent for some reviewers and controls the source volume
Comparisons (according to reviewers)
- Vs iBasso DC04 Pro—the DS2 has a more forward presentation, bringing vocals closer to the listener, while the DC04 Pro is more upfront and intimate with instrument presentation
- The DS2 offers improvements in dynamics and sound aspects compared to the Fosi Audio DS1
Takeaway: The Fosi Audio DS2 is a budget-friendly and powerful portable DAC/Amp that delivers clear and detailed sound, especially through its balanced output. It's a good option for those looking for an affordable upgrade to their audio experience on the go.
Video review
Our take on the brand
Note that this is a discontinued product. You may want to visit the brand's page here to browse their newer products.
What reviewers think
Magazine reviewers and YouTubers have tried this product—so we've summarized their strongest opinions below.
Product Strengths
- Beautiful build with a solid and high-quality feel
- Lovely smooth volume control
- Very noticeable bass depth goes down deep, providing a rich, deep bass sound
- Refined, smoother, warmer, and more organic/analog sound
- Lightweight, making it easy to carry around
Product Considerations
- The BU1 tends to err on the bass-heavy side, which may not be suitable for bass-heavy headphones
- Easy-to-throw gain switch can accidentally damage sensitive IEMs
- USB micro is not as durable as USB-C
- Lacks Bluetooth connectivity and balanced output
Takeaway: The BU1 is a well-built and lightweight DAC/amp that significantly improves sound quality, especially in bass depth, making music sound richer and more refined. It could be worth buying if one wants to enhance their smartphone or computer audio experience with a warmer and more analog sound.
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