SMSL DO400 Review

UI and Usage

Connection

Like most modern DAC, the SMSL DO400 can output a line-level output, and work as a pure Digital-to-Analog-Converter, or feed a power amp with a variable-level output, like a pre-amplifier. Bonus point, you can even use both outputs at the same time, or just one at a time (XLR/RCA), in case you only use one kind of amp with this DAC.

And, thanks to its comprehensive I/O, the DO400 became, once again, the hub of all my sources. If I mainly used the USB port, the DAC was easily paired with every gear I own, from a streamer (the iFi NEO Stream in this case), a computer (with the Toslink input), a CD-Player (Toslink input), or even my XBOX (HDMI with my home-theater amplifier pass-through function).

But where the DO400 surpasses its predecessors is in the addition of a comprehensive set of headphone outputs on the front panel. This improvement was initially introduced with the DO300EX, which Yagiz tested some time ago, but now it has been expanded to include two balanced outputs + one unbalanced instead of just one of each.

Thanks to that, this new device doesn’t need a separate headphone amplifier, like the DO200 / DO200MKII, and can be used straight out of the box, paired with a computer and a good headset. Sure, putting the SMSL HO200 behind elevates the final render, but for anyone seeking an all-in-one desktop DAC/AMP like the FiiO K9, the DO400 looks like the new go-to.

In my personal setup, I linked the RCA outputs to my KEF LS50 Wireless, and chose the old-but-lovely Audeze LCD-3 as my main headphone, plugged through the XLR 4-Pins output. And, out of curiosity, I kept the NuPrime STA-9 linked to the XLR 3 pins ports, so that it can feed a more classical stereo setup.

Quite nice if you ask me.

Everyday Use

As a dedicated desktop solution, the SMSL DO400 is simply perfect.

I replaced my previous DO200+HO200 stack with the new one, plugged a power supply, linked the DAC to my MacBook with an USB cable, and connected my Audeze with the stock XLR 4-Pins cable.  Once set up, the DAC was immediately recognized by both my PC and Mac, allowing me to choose which outputs to activate: XLR, RCA, Headphone out, or all simultaneously.

Bluetooth remains a nice addition, though for optimal performance, this DAC ideally should be connected to a real Wi-Fi streamer. And for those with an HDMI-compatible streamer or any source with I2S outputs, I’d recommend sticking to HDMI and USB for the best performance..

Finally, while I previously criticized the DO200’s scroll wheel, I must say that the new one on the DO400 is a vast improvement. Controlling the volume on a daily basis has been a seamless experience and my only issue came from the lack of a “back” button – you always have to wait until the screen comes back to the first page.

Full Menu

For those curious, if you want to dig inside the menu, those settings come as:

• Inputs: USB/BLUETOOTH/OPTICAL/COAXIAL/AES-EBU/I2S-HDMI
• Outputs: All Line OUT / Headphone OUT / Balanced / Unbalanced
• PCM Filter: Filter off / Minimum Phase / Apodizing /  Fast Linear / Slow Linear / Slow Minimum / Fast minimum / Low Dispersion I didn’t hear a real difference though
• HPA gain: Low / High (for your headphone out gain)
• Sound color: Rich 1/2/3, Tube 1/2/3, Crystal 1/2/3, Standard // if you want to change the color of your sound
• Pre-mode: Vol fixed, volume is fixed on max output level // Vol Variable, volume can be adjusted, like a pre-amplifier
• FN Key: you can choose which key to assign to fn on the remote : Outputs/Bluetooth/Phase
• DPLL: a special function embedded in ESS series products, that allows you to adjust the DPLL and find the right balance between anti-clock jitter and input tolerance. 15 different settings!
• I2S mode: normal/inverted // only relevant when you connect an HDMI source
• I2S DSD Channel: same as above
• Audio Phase: NORMAL (2+,3-) or INVERTED (2-,3+)
• Dimmer: you can set up how long the screen will remain lit after use (5 – 60 seconds)
• Brightness: 6 levels of brightness
• Reset: as it says

Overall, with a whole set of new setting added on this version, the DO400 remains a very quirky device with LOTS of features that will please the geeky audiophile – as I am.

On that good word, let’s check the specs.

The review continues on Page four, after the click HERE or by using the jump below.

Page 1: About the brand

Page 2: Design & Build Quality, UI & Usage 

Page 3:UI & Usage 

Page 4: Specifications, Bundle

Page 5: Sound performances