SMSL D400EX

HiFi, DAC
SMSL D400EX — Budget Giant Killer DAC

SMSL, like Topping, has been part of the Chinese measurement-audio revolution — companies delivering extraordinary technical performance at prices that make established brands nervous. The D400EX uses dual ES9039Q2M chips and measures absurdly well for its price. But does technical excellence at a bargain price mean it’s actually better than the competition?

Build & Design

Compact desktop form factor with an informative front display. Build quality is good for the price — solid aluminium case, clean layout. Inputs include USB, coaxial, optical, and Bluetooth. Both RCA and XLR balanced outputs are provided. It’s not going to win design awards, but it’s functional and well-made.

Sound

Character

Clean, transparent, and revealing. The D400EX sounds like what it measures — exceedingly low distortion with a neutral tonal balance. Music is presented with precision and clarity, without added warmth or coloration. Amir at ASR measured it with outstanding SINAD figures, placing it among the best regardless of price.

Detail & Resolution

Excellent. The D400EX resolves detail as well as DACs costing three or four times the price. The noise floor is vanishingly low, dynamics are clean, and stereo imaging is precise. This is the level of technical performance that makes the “expensive DACs sound better” argument increasingly difficult to defend.

Comparisons

Against my RME ADI-2 DAC FS, the D400EX matches or exceeds it in pure DAC performance at a fraction of the price. The RME wins on features (parametric EQ, crossfeed, headphone amp, display), build quality, and software refinement. Against the Denafrips Ares, the SMSL is more technically accurate but less “musical” — the trade-off between measurement and character.

DMS has discussed the “DAC wars” phenomenon where Chinese manufacturers are commoditising high-end performance, and the D400EX is exhibit A. Whether you value character or transparency determines which side you fall on.

Verdict

Pros

  • Extraordinary technical performance for the price
  • Clean, transparent sound
  • Comprehensive connectivity
  • Balanced outputs included

Cons

  • Sound can feel sterile to character-seeking ears
  • Build quality is good, not premium
  • Software and UI less refined than RME
  • Brand prestige may matter to some

Ratings:

  • Build & Design: 7 / 10
  • Sound: 8.5 / 10
  • Features: 7.5 / 10
  • Value: 9.5 / 10

The D400EX is the DAC that makes you question everything you’ve spent on DACs. Technical excellence, democratised.