Sometimes the best DAC is the one that’s small and affordable enough to fit your space (and your wallet). The SMSL D1 is a tiny DAC which offers all the basics you need, and even something more, while keeping the footprint really really small – it is barely bigger than a box of mints. And the best part is that despite being super affodrable and very small, it does not compromise on quality, sound or otherwise.
Disclaimer: I received a unit directly from SMSL for the purpose of this review. The SMSL D1 retails for $71.99. Additional information on the official product page.
TL;DR: recap
| Pros |
Cons |
| + Simple and easy to use
+ Good variety of connection options + Neutral sound signature + Super affordable |
– …none? |
Rating: 10/10
Packaging & Accessories
The cardboard box (with generous padding) includes the device itself, together with a USB-A to USB-C cable and a manual.
Design & Build
The SMSL D1 sits firmly in the company’s tradition of minimalist design. The device looks like a simple black box, with some text on the front. The front has no buttons or switches: it is, in fact, just a glass panel which responds to touch. There are two touch-sensitive areas: one on the left hand side, to change the input, and one on the right hand side, which allows you to turn the device on and off. The touch buttons are very responsive, so much so that the response to input is instant. The input area includes a list of the inputs with a status LED next to each and an extra LED for DSD; the latter lights up in green when DSD is playing and red when the unit is turned off.
The back is where all the connectors are. There are two USB-C ports, one that only provides power and a second which can carry data as well, an optical port, a coaxial port and a stereo RCA output. I have asked SMSL why they chose to provide a second USB-C port and they said that it is because sometimes computers do not offer enough power, or reliable enough power, so a second USB port allows one to use the device with a computer (or tablet, or phone) even if that device cannot provide the required power.
The chassis is made of aluminium and there are four rubber feet on the bottom which keep the device still on the surface. Build quality is, as expected with SMSL, superb.
Features & Specs
In terms of inputs and outputs, the SMSL D1 focuses on the fundamentals: you have USB, coaxial and optical inputs, and stereo RCA output. That’s it. This is enough, however, to use the SMSL D1 as a desktop DAC or as an addition to an already-existing system where you want to add (or update) the digital side and keep the analogue one.
The SMSL D1 offers no advanced features such as filters; it is, in fact, stripped down to the simplest functionality: it is a pure DAC which focuses on delivering sound without faffing about.
The SMSL D1 is compatible with Windows though you need to install a driver to unlock compatibility with higher resolutions), macOS and even Linux. Compatibility with Linux means that it will work with devices such as the Steam Deck and Steam Machine, and I can attest it works as I use Linux exclusively on my devices.
SMSL D1 |
| Input | USB (up to 32 bit / 768 kHz PCM, up to DSD512) Optical, coaxial (up to 24 bit, 192 kHz) |
| Output impedance | N/A |
| Frequency response | N/A |
| THD+N (@1 kHz) | < 0.00038% |
| SNR | 119 dB |
| Crosstalk | N/A |
Inside the SMSL D1 is a ROHM BD34352EKV DAC chip, which is an unusual choice: in fact, this is the first time I’ve ever tried a device including this chip. It is made by the Japanese company ROHM and sports specs which are close to that to the more well-known ESS ES9018K2M: an SNR of 126 dB and a THD+N of -112 dB (by comparison, the ESS model stands at 127 dB and -120 dB, respectively). SMSL does not publish any specification regarding the amplification stage.
I have asked the company why they chose the ROHM chip, considering it is a lot less popular than alternatives from AK and ESS; they said that they chose it because it offers excellent audio performance with “a very natural, detailed and refined audio presentation, which matches the tuning philosophy of the D1.”
Sound
I have tested the SMSL D1 with a pair of Edifier MR5 active speakers.
Although the SMSL D1 is an entry-level DAC, it offers very strong performance which leaves nothing to be desired. In fact, it sounds perfectly neutral, with no deviation from the ideal linear response, and it doesn’t present any noise issues (hiss, hum…) either. It is, in most ways, comparable to any DAC out there, including the high-end ones. Transients are as fast as you expect them to be, and details are all there.
Final Thoughts
The quest for perfect audio is like the one for the Holy Grail: it is never going to end. And yet, in this constant search, we can find things that are worth taking a look at. Very interestingly, it is increasingly the case that such things are entry-level devices, and this appears to be true for the SMSL D1 as well. It offers great sound quality and functionality while keeping the price below $100, which is significant. In less than a decade, we have reached the point where the D1 costs nearly half as much as the Topping D30 while also offering significantly better performance and functionality. In short, then, there’s nothing not to like about the SMSL D1 – in fact, it is a great little device which offers everything you need at a very competitive price. And that’s why it gets my full seal of approval.
