SMSL DO400 DAC And Headphone Amplifier Review (1) – Will The Circle Be Unbroken?
With its new $499 DO400, SMSL officially has released more DACS and amps than Trump has felony indictments. In the sub-$250 range, SMSL’s gear is a no-brainer, with better build and (to my ears) more refinement than comparably-priced Topping, Fiio, etc. Moving up to the $500 level, however, and the competition is a bit thornier, with well-regarded players from Ifi, Burson and the like, as well as more mainstream Western brands like Schiit and Pro-Jekt.
If nothing else, SMSL packs a ton of features into the DO400—a high quality DAC (ES9039MSPRO chip with w/MQA decoding), digital preamp, high powered headphone amp and LDAC/AptX Bluetooth streaming. Aesthetics, UI and build are standard SMSL, albeit with a slightly revised display window which shows input source, sampling rate, etc.
Connectivity is impressive, with balanced and unbalanced outs, and a panoply of digital inputs. Curiously, there are no analog inputs, which limits the sources you can pair it with. Stepped volume control is very sensitive and, as previously, the single control knob on the face is very intuitive and user-friendly.
I road-tested the DO400 with an old Sony ES CD player and my desktop PC; I also used it as a preamp with my trusty Parasound HCA power amp as well as SMSL’s pocketbook-sized, Class D A300. I tested its headphone section with the 300 Ohm Sennheiser 650, the 60 Ohm Koss KSC75 and a gamut of sensitive (16-32 Ohm) IEMs, including the fantastic new BGVP DM9.
As a DAC, the DO400 epitomizes SMSL’s house sound—wide soundstage, prominent, well-controlled bass, a forward, driving midrange and very crisp, detailed high end. Notes are weightier than on SMSL’s cheaper offerings like the SMSL SU-6 or C100, although compared to SMSL’s fantastic, comparably priced SMSL SU-9 the DO400 sounds slightly brighter and less-smoothed over; there’s an analytical quality to the treble end which gives a hyper-pixilated sheen to piano keys and cymbal hits.
Tonality is nonetheless quite live-sounding, if occasionally exhausting. Like the SU-9, the various sound colors and DSD filters have a very subtle effect (more pronounced through the headphone section), though technoids will enjoy.
Background is dead quiet and instrument separation is very clean. Largely because of these qualities, it’s really excellent as a preamp—transparent yet energetic, with considerable presence and drive even at lower volume. It sounds like an expensive piece. (Note that Bluetooth sounds fine, though not transcendent; esp. when contrasted to the hi-res and even CD material I used for testing, I felt little urge to return to it).
I compared the DO400’s DAC to my audio chum’s Chord Mojo ($500ish), which has a similarly dynamic, open-sounding presentation. The Mojo sounds somewhat bassier and fuller, perhaps truer to source, but doesn’t present some the very fine detail you’ll hear on the SMSL. Sonically, we could not pick a clear winner between the two (the Mojo being better matched to heavy rock and the SMSL to subtler fare), though the SMSL has much superior UI and more functions.
As a headphone amp, the DO400 is characterized by its power, clarity, and precise instrument separation—every note is cleanly articulated and there’s no bunching of performers. There is a bit of unnatural adrenalized quality to the presentation—drums in particular have a loud, hyped-up quality even on quieter passages.
This effect is, predictably, less of a factor on less sensitive phones—the Senn HD 650 (which can sound lethargic without sufficient power) took on a palpably physical, toe-tapping presence while the cheap, tough-to-drive Koss presented much better bass control and sounded bigger-than-usual.
More efficient phones, however, tended to lose some composure, especially at the low end—the BGVP DM9, which are meticulously sculpted and accurate through my mobile and a dongle, sounded overdriven and billowy through the DO400 even without the HPA mode engaged.
In contrast, my cheaper headphone amps like the (tube) Aune T1 and the Pro-Ject Head Box presented significantly less detail, a thinner note presentation and a narrower stage, but were actually a better match for the DM9—warmer and more coherent, with less unruly bass, However, the DO400 has a noticeably quieter background–the difference is like being live in the studio vs. listening to a vinyl rig.
So the DO400 is not a paragon of neutrality, and as a headphone amp it pairs better with higher impedance headphones. It does however have a lot of that elusive PRAT and is a clear step above SMSL’s very credible entry level DACs; especially considering its preamp functionality, registers as a lot of machine for the money. Another winner for the relentless SMSL machine.
Disclaimer: This unit was provided to me by Aoshida for review purposes and can be purchased here (tested at $499):
https://aoshida-audio.com/products/smsl-do400
I have passed this on to Durwood for his (generally better-informed) take; what he does with it is entirely up to him.
Specifications SMSL DO400
