SMSL DO100

Introduction​

I usually start my reviews by introducing the manufacturer of the product I’m currently reviewing, but come on, you know SMSL. One of the leading manufacturers of DACs and amplifiers for years now, offering an extraordinary value and one of the best measuring devices in the world of audio.
So, straight to the point, the hero of today’s review, the DO100. This is a pretty affordable DAC coming at $239. No MQA support, no pre-amp, just a DAC that is focused purely on good audio performance. With its CNC-machined aluminum case, balanced output and Bluetooth 5.0 with LDAC on board it seems like a fantastic entry-level DAC for just about everybody.
We’re pretty much used to SMSL stuff sounding as neutral as it gets. They’re just pushing the prices of their devices lower and lower, delivering better performance. Let’s see how it went this time.

Packaging​

The unboxing experience of the DO100 is pretty straightforward. It comes in a minimalistic white box with a clean graphic of the DAC on the top lid. Inside you’ll find the DAC, a USB cable (more later), a power chord and a remote.
There’s nothing else to say about it . The quality of included cables is just decent, and the remote has the most important functions like turning the device on/off, changing the volume, muting the device, etc.

Design, Build and I/O​

The DO100 is made of CNC machined aluminum and it feels pretty solid. It’s a rather small DAC, but it feels substantial and dense in hand. The size feels just about perfect for any desk scenario.

The actual build quality is pretty good, there are no sharp edges, it stays in place thanks to the rubber feet, and looks just great paired with the HO100 amplifier. It has a built-in screen that shows the selected input and the quality of the file currently playing. Lastly, there’s a knob to select the input on the front panel. This is a pretty simple DAC that focuses on only the most important aspects.
From the design point of view, this is yet another SMSL DAC. It’s black, minimalistic, and just an aesthetically pleasing device. Nothing to write a book about, but certainly nothing to criticize. I somewhat miss the times when different DACs really looked different, but I actually understand this kind of approach. This design has been here for years, it’s safe and just good.

Let’s talk about the I/O, and I’m going to start by saying that – SMSL, BRAVO. This DAC doesn’t have a USB-B input, but a USB-C one. Finally, the audio market is entering the year 2018. Jokes aside, this should be a thing for years now and I’m glad SMSL went this way. I can finally plug a DAC into my MacBook without any adapters, just a single USB-C to USB-C cable. This is so good.
Other than the USB, we’ve also got a COAX and Optical input to connect to an external CD transport or a TV, and an antenna screw (of course, the Bluetooth antenna is included in the box to screw in). On the output side, you’ll find both XLR and RCA, so this DAC is pretty universal when it comes to pairing with different amplifiers.
Lastly, the DO100 has a built-in ultra-low-noise power supply, so say goodbye to chunky power supplies laying around on the floor. All you need is just a simple power cord and you’re ready to go. To see a quality power supply in a device this small, with all its features is pretty impressive, to say the least.

Tech​

Let’s talk tech for a second. First up, the DO100 is built around a dual ES9038Q2M DAC chip, and it used four OPA1612 OP-AMPS.
The Bluetooth chip used is the Qualcomm QCC5125, and it supports LDAC 24bit/96kHz, APTX/HD, SBC and AAC, so when it comes to Bluetooth codes for audio, you’re pretty much set.
The DO100 can decode DSD512 natively and it supports PCM up to 32bit/768kHz.
This combination of different components gives you all you need when it comes to connectivity and different quality of music files. It does not support MQA, so Tidal users should have this in mind (no, I’m not going to comment on the whole MQA situation).
When it comes to the measurements, I’m not measuring stuff myself, but I’m pretty sure you’ll find them online somewhere. I’m pretty sure this will measure as good as it gets, it’s an SMSL DAC.

Sound​

Okay, okay, you’re not willing to spend a lot, but you still want ultra-high-quality audio don’t you? So, how does the DO100 sound? Well…it sounds incredibly clean and neutral, as neutral as it gets actually. SMSL has been pushing some ridiculous numbers when it comes to measurements lately, and it all shows in the sound quality and signature of their devices, and the DO100 is no different.

This is a fantastic first “high resolution” DAC for all of you audio rookies that just want a no-bull performance at a fair price. I know audio can be confusing, all these numbers, specifications, and the subjectivity of it all, it’s really easy to get lost. So, I’m going to answer your question right now – is the DO100 worth buying if you’re looking for a budget DAC that sounds great? Yes.

I won’t be getting into different frequencies this time, as this device is so neutral that I don’t actually see the point. You’re basically getting a dead-flat sound signature, and if you want any coloration of your audio, you better have headphones that do that. When I pair the DO100 and HO100 combo with my Hifiman Edition XS, the sound is so neutral that it actually amazes me. That quality would have cost you at least 5 times more as recently as 5 years ago. This is the thing that I really like about the audio market nowadays…stuff gets cheaper, and better, at the same time.

So, is a dead-neutral DAC good for you if you’re in the market for your first proper DAC? Well, it depends on a few factors. First, do you really want a neutral tonality? This might be great to get to know the “benchmark” of headphone audio, the way it all “suppose to sound like”. More experienced audiophiles actually tend to go for the sound that is not neutral but to know what kind of sound coloration you like, you have to get your basics done.
The question is – is the DO100 worth getting at $239, when there are things like the JDSLabs Atom DAC+ and Schiit Modi DAC at $119 and $129 respectively? It actually is. First of all, the DO100 is built better than both of them, it has a built-in power supply, balanced outputs, Bluetooth, and remote control. Both Schiit and JDSLabs are brilliant devices (we reviewed both of them), but the DO100 is just a more polished and feature-packed device than both.
When it comes to the actual technical performance, the DO100 doesn’t sound like a $239 DAC. It’s clean, fast, detailed, and well-controlled throughout the entire frequency response. The bass can get very low, the midrange is just neutral and “proper” sounding, and the treble extends all the way to the top octaves, without a hint of sharpness. Take note though, as if you’ll use bright-sounding or overly sharp headphones, the DO100 will not counter it in any way. If you’re very sensitive to the upper frequencies, I’d suggest smooth and rather dark-sounding headphones to pair it with.

There’s one last thing that is worth mentioning. I’ve used the DO100 with different headphones, even the Summit-Fi ones like the Hifiman Susvara, Meze Elite, and Final D8000 Pro. I never had a feeling that this little DAC is holding anything back. Of course, I’ve heard a better sound coming out of these headphones, but at this price, this is very impressive. We’re talking about headphones that cost 20+ times more than the DO100, and they actually sounded great with it.
As for the pairing, the DO100 will pair with everything just great. It will all depend on the type of experience you’re looking for. This is not a DAC that will change the sound signature of your system, quite the opposite actually. It will give you a very neutral signal, and what you’ll do with it next is up to you.

Pairing suggestions​

Pawel cut the crap and give us some ideas of what to pair the DO100 with! Okay, okay…fine.

1. SMSL DO100 + SMSL HO100 + Hifiman Edition XS

This is the ultimate neutral and flat-sounding system you can get at sub $1000. Every piece of equipment in this setup is just neutral and technically impressive. This setup will give you an uncolored sound that is filled with detail and resolution. I’ve said it once, and I will say it again – You’d have to pay thousands for this kind of performance a couple of years ago, and now it can be yours for under thousand bucks. What a time to be an audiophile.
2. SMSL DO100 + SMSL HO100 + Drop + Hifiman R7DX

Similar to the previous system, but now with a closed-back pair of headphones and even more affordable, actually quite a lot more.
The R7DX (review here) is a closed-back version of the legendary Sennheiser HD600/6xx in some aspects, and if you really need closed-back headphones…this is the setup to get. Neutral, comfortable, functional, and it does everything right. Movies, music, gaming, you’re pretty much set with everything.

3. SMSL DO100 + xDuoo TA-26 + Sennheiser HD6XX

Now we’re getting into something quite different. Here we have that dead-neutral DO100, but it’s paired with a proper all-tube amplifier and a high-impedance classic, the HD6xx by Drop. This setup will be much smoother and warmer sounding than the two previously mentioned, giving you a more colored and “prettier” sound performance. If you want to taste something else, this might be a great way to start. The DO100 makes sure the rest of the system gets a proper quality to work with, the TA-26 will give it that tube goodness, and the 6xx…yeah, this is just class.

4. SMSL DO100 + XI Audio Broadway S + Hifiman HE1000se

Yes, you read it correctly. No, I haven’t gone mad. This setup actually sounds incredible. The DO100 has all the technical capabilities needed for both the Broadway S and the 1000se to shine. Yes, you can get an even better sound with a better DAC. But if you don’t believe in DACs or just simply want this one, this is an absolutely great system that sounds marvelous.

5. SMSL DO100 + SMSL HO100 + Any pair of well-tuned IEM

The star of the show. While listening to the DO100 I was pretty impressed, but when I tried this combo with my Fir Audio Xenon 6 CIEM ($3899) I was absolutely blown away. SMSL points out this “super clean” aspect of these devices, and they’re not lying. This combo has virtually no hiss, pitch-black background, and exceptional clarity. If I listened to this setup and you would tell me that I’m listening to the XENON6 out of a high-end DAP, I would have probably believed it.

Summary​

The SMSL DO100 is a highly capable DAC coming at a very fair price. It’s well-built with its CNC machined aluminum shell, has neat functions like Bluetooth, a remote control, and balanced output, and most importantly…it’s hyper-clean and neutral sounding. If you’re looking for a DAC that does it all in the $250 market, the DO100 is definitely a wonderful choice.

Highly Recommended.

Gear used during this review for the sake of comparison and as an accompanying equipment:

• Headphones – Hifiman Susvara, Final D8000 Pro, Audeze LCD-X 2021, Hifiman HE1000se, Abyss Diana PHI, Drop + Sennheiser HD8XX, Crosszone CZ-1, HEDDphone, Meze Empyrean, Drop + Hifiman R7DX, Sennheiser HD6xx, Hifiman Edition XS, Fir Audio XE6, Final A8000,
• Sources– Topping D90se + A90, Ferrum OOR, EarMen Tradutto, JDSLabs Atom DAC+/AMP+, Cayin N3Pro, xDuoo TA-26, XI Audio Broadway S, SMSL HO100

Big thanks to Aoshida-Audio for providing the DO100 for this review. I wasn’t paid or asked to say anything good or bad about this product, all of the above is just my personal, unbiased opinion. Aoshida-Audio hasn’t seen this review before publishing it.
You can get your SMSL DO100 on Aoshida-Audio here.