SMSL DO400 Review: Ranked #1 of 43

Last updated: October 11, 2026

The SMSL DO400 ranks #1 out of 43 total DAC and Headphone Amp Combos for sound quality. See all Headphone Amps and DACs rankings for every top pick.

Brand: SMSL

Prices on this page were last checked October 11, 2026 at 4:59 PM UTC. Product prices and availability are accurate as of that date/time and are subject to change; the price and availability shown on Amazon at the time of purchase will apply to the purchase of this product.

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#1 SMSL DO400: $499.00 Amazon eBay

Pros: Audio Science Review measured 123 dB SINAD, so its noise and distortion are transparent. A rated 3 W into 32 ohms and 700 mW into 300 ohms drives nearly any headphone, through 6.35 mm, 4.4 mm or 4-pin XLR outputs. Inputs cover USB, optical, coaxial, AES/EBU, I2S and LDAC Bluetooth, with RCA and XLR outputs for powered speakers.

Cons: It costs more than the D&A Alpha and SMSL RAW-MDA1, which share its rating and also measure transparent. At 1,450 g it is a full size desktop unit.

Balanced OutputYes (4.4 mm, 4-pin XLR, XLR line out)
Bluetooth CodecsSBC, AAC, aptX, aptX HD, LDAC
DAC ChipES9039MSPRO
Device TypeDAC and headphone amp
Dimensions9.6” x 1.7” x 7.3” (245 x 42 x 186 mm)
Headphone Outputs6.35 mm, 4.4 mm balanced, 4-pin XLR balanced
InputsUSB, optical, coaxial, AES/EBU, I2S, Bluetooth
Output Power (300 ohms)700 mW (manufacturer rated)
Output Power (32 ohms)3,000 mW (manufacturer rated)
OutputsRCA, XLR
SINAD123 dB (measured by Audio Science Review)
Weight3.2 lbs (1,450 g)

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