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
Bloggers and YouTubers have tried this product—so we've summarized their strongest opinions below. Links to full reviews follow.
Product Strengths
- The DO400 is a versatile device, serving as a DAC, preamp, headphone amplifier, and Bluetooth receiver
- It offers a highly resolving and transparent sound, with a measured dynamic range of 133dB on its XLR output and 126dB on its headphone output
- It has very tight control over the drivers, sounds quite dynamic and clean, and delivers a punchy sound
- The DO400 features extensive I/O with HDMI, USB, XLR 4-Pins, and Pentaconn 4-Pins
Product Considerations
- It does not have analog inputs, which limits the sources one can pair it with
- The DO400's case cover is steel, and the rotary knob wobbles
- Some may find its sound signature a bit too linear for some genres
- The remote control is plastic-y
- The speedy nature of the ESC by Silicon might result in a less impressive initial kick in the eardrums via headphones, compared to the XLR and RCA outputs
Comparisons (according to reviewers)
- Compared to the Topping DX7 Pro Plus, the DO400 is more organic and dynamic sounding
- Compared to the Topping DX5, the DO400 offers noticeably better line output
- Compared to the Chord Mojo 2, the Chord Mojo 2 sounds better when used as a DAC, offering better detail retrieval and a richer tone timbre, but the DO400 has more power
- Compared to the SMSL SU-9, the DO400 sounds slightly brighter and less-smoothed over—there's an analytical quality to the treble end
Takeaway: The SMSL DO400 is a great-sounding all-in-one unit that offers a lot of features for the price. Its noiseless performance with IEMs and ability to drive most headphones make it a worthwhile purchase.
All
DO400
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Manufacturer details
- DAC Chip: ES9039MSPRO
- XMOS Processor: XU-316
- PCM Support: up to 32bit/768kHz
- DSD Support: up to DSD512
- Headphone Output Power: 6W (16 ohm), 3W (32 ohm)
- Bluetooth Version: 5.1
- Bluetooth Codecs: LDAC 24bit/96kHz, APTX/HD, SBC
- Headphone Outputs: 4-XLR, 4.4mm, 6.35mm
Brand highlights
Taking a step back to look at reviewers' thoughts of the brand's entire lineup—not just this product—what stands out most is the following:
- SMSL amplifiers, particularly the AO series, offer a versatile feature set, including USB DAC functionality, Bluetooth connectivity, and subwoofer outputs, making them suitable for diverse audio setups, often at an affordable price.
- They incorporate quality components, such as Infineon Class D amplifier chips, NJRC potentiometers, and TI op-amps, reflecting a deliberate choice to balance performance and cost.
- SMSL DACs often provide a neutral and transparent sound signature, aiming for accurate audio reproduction with excellent detail retrieval.
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Used
SMSL
What if you spend more?
Each channel uses 40 pcs, and total 80 pcs selected low-noise op amps in parallel design; The distortion is as low as 0.00006%, and the SNR is as low as 137dB! High output power, 16 ohm output power up to 11.5W, 32 ohms up to 5.5W; Relay Switching Volume attenuator,completely avoid imbalance between the left and right channels! 3 gears gain control, low gain is specially optimized for IEM; Pre-out function, can be used as Hi-End pre-amp; Tempered glass optically bonded IPS display screen Ultra-compact design, very suitable for desktop system; High precision low-temperature drift resistance, performance is not affected by temperature; High-quality relay and non-impact sound design; 20Hz to 100KHz(-0.5dB) frequency response; The headphone amplifier has comprehensive protections such as DC, overvoltage, and overload protection; Built-in high efficiency and low noise power supply system
Product Strengths
- Very sturdy and well-built headphone amplifier made out of aluminum
- Plenty of power and driving capabilities for both high impedance headphones and low impedance planars
- Tonality is well balanced with nothing emphasized or lacking across the frequency spectrum
- Sounds very natural and coherent, with no edgy or rough parts in its performance
- Offers good detail retrieval, separation, and layering of instruments and vocals
Product Considerations
- As a preamp, sound staging isn't particularly wide or deep compared to dedicated preamps
- The black volume knob is described as plasticky and some reviewers wish it was silver to match the chassis
- Lacks a 12V trigger, which would be a much-needed option
- Can run hot
- No auto-standby mode
Comparisons (according to reviewers)
- Vs Topping A90D: SH-X adds a slight hint of warmth in the bass section and is slightly more alive–engaging sounding, while A90D sounds more ruler flat
- Vs aune S17 Pro: SH-X can compete head to head with S17 Pro in 50mA mode, but S17 Pro edges it out in 100mA mode sounding tonally richer and fuller
Takeaway: The SMSL SH-X is a beautifully built and powerful headphone amplifier that offers a clean and transparent sound. It is a great choice for those wanting a high-performing amplifier with versatile connectivity options.
Video review
Our take on the brand
Fully balanced discrete design for ultra-high power output. The distortion is as low as 0.00006%, and the SNR is as low as 133dB! High output power, 16 ohm output power up to 15W, 32 ohms up to 7.5W; Relay Switching Volume attenuator,completely avoid imbalance between the left and right channels! 3 gears gain control, low gain is specially optimized for IEM; Pre-out function, can be used as Hi-End pre-amp; Tempered glass optically bonded IPS display screen Ultra-compact design, very suitable for desktop system; High precision low-temperature drift resistance, performance is not affected by temperature; High-quality relay and non-impact sound design; 20Hz to 100KHz(-0.5dB) frequency response; The headphone amplifier has comprehensive protections such as DC, overvoltage, and overload protection; Built-in high efficiency and low noise power supply system; Equipped with remote control, full-function remote control.
Product Strengths
- Delivers plenty of power for almost all headphones on the market
- Has a neutral sound signature with good detail retrieval throughout the frequency spectrum
- Balanced output provides greater clarity, instrument separation, and a wider soundstage
- Features a redesigned and modern-looking user interface with simple controls
- Offers clean sound, remote control, and precise volume control, suitable for a wide range of headphones from IEMs to difficult-to-drive models
Product Considerations
- Single-ended output sound is good, but the balanced output is noticeably better—meaning a balanced cable is recommended
- Compared to the Topping A70 Pro, it has less weight and grunt in the bassline
- The volume adjustment process can be a little choppy when using the soft volume control
- Does not have a DAC inside, it is just a headphone amplifier with analog inputs only
Comparisons (according to reviewers)
- Vs Topping A70 Pro: H400 has a quicker, more nimble bass, and a more lively and sparkly sound in the higher frequencies, while A70 Pro is bassier and slightly warmer
Takeaway: The SMSL H400 is a well-built, powerful headphone amplifier that provides great sound quality, especially when using balanced output. It is a great choice for anyone looking for a reliable amplifier with a clean interface and plenty of features.
Video review
Our take on the brand
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
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 competes at this price?
Our Summary
Product Strengths
- 'Ridiculous power for a headphone amp' with 6 watts at 16 ohms and 3 watts at 32 ohms
- Able to drive everything from IEMs all the way through to the most power-hungry headphones
- Very low noise floor
- All-metal chassis with a nice matte-black finish
- Clean, smooth, and detailed sound, without anything to complain about
Product Considerations
- Volume knob is shallow and not particularly enjoyable to grasp
- Can be a little edgy up top with certain headphones
- A little more articulation and crispness at the leading edge of notes would be preferred
- Some found soundstage smaller than expected
- Gain is still a little too high for IEMs
Comparisons (according to reviewers)
- Compared to the SMSL SH-8S, the HO200 has a multi-level gain switch with low, medium, and high and is preamp capable, but the SH-8S is more detailed and textured
- Compared to the Topping A90, the HO200 is a 'baby brother'
- Compared to the JDS Labs Atom Amp, it is a lot more dynamic in bass
Takeaway: The SMSL HO200 is a powerful and versatile headphone amplifier that doesn't sound sterile and boring. It is a solid choice for anyone who wants a clean and detailed sound with enough power to drive a wide range of headphones and IEMs.
Video review
Our take on the brand
Our Summary
Product Strengths
- Plenty of power and headroom
- Wide three-level gain jump
- Can be used as a pre-amp
- An excellent range of output options available, including 4.4mm, 4-pin XLR headphone outputs, and a 6.35mm interface
- Projects distant objects without much effort, and has excellent dynamic range
Product Considerations
- Can sound stiff and shouty on poor pairings
- Delineation gets hindered by dampened bite
- The volume wheel is quite small compared to how wide and chunky it is
- Short tip and travel though makes the analog toggles a bit more awkward to use
Takeaway: The SMSL H300 has plenty of power, can be used as a pre-amp, and is a wide staging amplifier projecting distant objects without much effort. It is a good option to consider if you are looking for an amplifier.
Video review
Our take on the brand
Our Summary
Product Strengths
- Sounds far better than the FiiO Q1 MK II because it uses two TI chips compared to the FiiO's one AK chip
- The balanced output is around 50% more powerful than the Q1 MK II
- For clarity and naturality, it beats the Creative E5 by a small margin
Product Considerations
- Battery life is around 7 to 8 hours at max, whereas the FiiO Q1 MK II has better battery life
- Some floor noise exists, which is not much on the FiiO Q1 MK II
- Feels slightly edgy and uncomfortable
- A simple accessory set exists, lacking bands or rubbers to tie the amplifier with your source
Takeaway: If you want a portable amplifier with superior sound quality because of its two TI chips, the SMSL SAP-11 is a great choice. It offers better sound compared to its competitors, especially if you don't need a built-in DAC.
Video review
Our take on the brand
Our Summary
Product Strengths
- Built like a tank and is a heavy brick
- The volume knob is smooth and made of metal, floating on a silicone suspension
- It has a protection circuit built-in
Product Considerations
- There's a slight buzz at low volumes with the doonoo zens that fades out when the volume is turned up
- The power switch is on the back
- The volume knob is on a silicone suspension, so it can be turned and keep turning—which can make the indicator point in the wrong direction
- Reviewer received the product after a long wait
Comparisons (according to reviewers)
- The Sings are is a better amplifier
- The SAP-1 probably beats the Magni and Heresy in build quality
Takeaway: The recgviNbkfbno9pQR is a well-built, simple amplifier that works well, especially for under $100. The recgviNbkfbno9pQR is great for adding headphone amplification to a pre-existing system that doesn't have a headphone amplifier.
Video review
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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
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