The SMSL SP400 ranks #10 out of 38 total Headphone Amplifiers for sound quality. See all Headphone Amps and DACs rankings for every top pick.
Brand: SMSL
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#10 SMSL SP400 Discontinued eBay
Pros: Audio Science Review measured a SINAD of 120 dB, so its noise and distortion are inaudible and it is transparent in practice. SMSL rates it at 6 W into 32 ohms balanced, enough for nearly any headphone including hard planar magnetic models. It adds XLR and RCA inputs, a balanced preamp output and a remote control for the volume.
Cons: It is no longer sold new, and at 1.33 kg it is a sizable desktop box. The Topping A50 III matches its rating with a slightly better 121 dB measurement, and it needs a separate DAC because it has only analog inputs.
| Released | 2020 (6 years ago) |
|---|---|
| Balanced Output | Yes |
| Device Type | Headphone amp |
| Dimensions | 8.9” x 1.7” x 8.3” (225 x 43 x 210 mm) |
| Inputs | XLR, RCA |
| Output Power (32 ohms) | 6,000 mW (manufacturer rated, balanced) |
| Outputs | Balanced preamp out |
| SINAD | 120 dB (measured by Audio Science Review) |
| Volume Control | Knob and remote |
| Weight | 2.9 lbs (1,330 g) |
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