Short answer: the SMSL D-6S. It ranks #9 of 30 DACs by measured performance, rated 4.8/5, at $199.99. The Sonnect SoundWire ranks #30, rated 2.4/5, at $165, $34.99 cheaper, which does not close the gap in measured performance.
The SMSL D-6S is the better-sounding option. Audio Science Review measured 122 dB SINAD, so its noise and distortion are transparent. The tradeoff: There is no volume control listed, so it relies on the amp or speakers downstream to set level.
The case for the Sonnect SoundWire: It turns a USB-C phone or computer into a source with two transformer isolated XLR line outputs, which suits connecting directly to powered speakers, mixers or PA systems. The tradeoff: Audio Science Review measured a SINAD of 85 dB, a level of noise and distortion that is an audible weakness.
Buy the SMSL D-6S. It is rated higher, and the $34.99 saving on the Sonnect SoundWire is not enough to make up the difference.
Still deciding? The full Headphone Amps and DACs rankings cover every ranked option.
Specifications Side By Side
| SMSL D-6S | Sonnect SoundWire | |
|---|---|---|
| Price | $199.99 | $165.00 |
| Ranked | #9 of 30 in DACs | #30 of 30 in DACs |
| Device Type | DAC | DAC |
| SINAD | 122 dB (measured by Audio Science Review) | 85 dB (measured by Audio Science Review) |
| Balanced Output | Yes (XLR line out) | Yes (XLR line out) |
| Inputs | USB, optical, coaxial, Bluetooth | USB-C |
| Outputs | RCA, XLR | 2 x XLR (transformer-isolated) |
| Bluetooth Codecs | SBC, AAC, aptX, aptX HD, LDAC | - |
| DAC Chip | ES9039Q2M | - |
| Dimensions | 5.9” x 1.7” x 5.1” (150 x 42 x 128.5 mm) | - |
| Weight | 1.6 lbs (710 g) | 0.3 lbs (140 g) |
| Volume Control | - | None (phone/PC volume) |
Related Amp and DAC Comparisons
How SMSL D-6S compares with other leading options:
- Topping D50 III vs SMSL D-6S
- SMSL D-6S vs SMSL DO200 MKII
- Fosi Audio ZD3 vs SMSL D-6S
- SMSL D-6S vs SMSL D200
- SMSL D-6S vs SMSL SU-6
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.
As an eBay Partner, we may be compensated if you make a purchase.
The Two Amps and DACs In Full
SMSL D-6S: $199.99 Amazon eBay
Pros: Audio Science Review measured 122 dB SINAD, so its noise and distortion are transparent. It offers USB, optical, coaxial and LDAC Bluetooth inputs with RCA and XLR outputs for an amp or powered speakers. It matches the rating of the Topping D70 Pro SABRE for far less.
Cons: There is no volume control listed, so it relies on the amp or speakers downstream to set level. DACs such as the Topping D70 Pro SABRE measure a touch cleaner at 123 dB, though they cost far more and the difference is not audible.
Full SMSL D-6S review and specifications →
| Released | Sep 2023 (3 years ago) |
|---|---|
| Balanced Output | Yes (XLR line out) |
| Bluetooth Codecs | SBC, AAC, aptX, aptX HD, LDAC |
| DAC Chip | ES9039Q2M |
| Device Type | DAC |
| Dimensions | 5.9” x 1.7” x 5.1” (150 x 42 x 128.5 mm) |
| Inputs | USB, optical, coaxial, Bluetooth |
| Outputs | RCA, XLR |
| SINAD | 122 dB (measured by Audio Science Review) |
| Weight | 1.6 lbs (710 g) |
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons
Sonnect SoundWire: $165.00 Sonnect eBay
Pros: It turns a USB-C phone or computer into a source with two transformer isolated XLR line outputs, which suits connecting directly to powered speakers, mixers or PA systems.
Cons: Audio Science Review measured a SINAD of 85 dB, a level of noise and distortion that is an audible weakness. It has no headphone output and no volume control of its own. The Samsung USB-C to 3.5mm Headphone Jack Adapter measures cleaner and rates higher for far less, although it lacks XLR outputs.
Full Sonnect SoundWire review and specifications →
| Balanced Output | Yes (XLR line out) |
|---|---|
| Device Type | DAC |
| Inputs | USB-C |
| Outputs | 2 x XLR (transformer-isolated) |
| SINAD | 85 dB (measured by Audio Science Review) |
| Volume Control | None (phone/PC volume) |
| Weight | 0.3 lbs (140 g) |
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons