Short answer: the Fosi Audio ZD3. Both are rated 4.8/5 (#15 and #9 of 30 DACs), and the Fosi Audio ZD3 costs $179.99 against $199.99 for the SMSL D-6S, with the ratings tied, the lower price decides it.
The case for the Fosi Audio ZD3: Audio Science Review measured 117 dB SINAD, so its noise and distortion are transparent. The catch: Its SINAD is a few dB behind similarly rated DACs like the SMSL D-6S, though both are transparent.
The case for the SMSL D-6S: Audio Science Review measured 122 dB SINAD, so its noise and distortion are transparent. It supports LDAC Bluetooth, which the Fosi Audio ZD3 lacks. The tradeoff: There is no volume control listed, so it relies on the amp or speakers downstream to set level.
Buy the Fosi Audio ZD3. Both are rated the same, and it costs $20 less than the SMSL D-6S.
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Specifications Side By Side
| Fosi Audio ZD3 | SMSL D-6S | |
|---|---|---|
| Price | $179.99 | $199.99 |
| Ranked | #15 of 30 in DACs | #9 of 30 in DACs |
| Device Type | DAC | DAC |
| SINAD | 117 dB (measured by Audio Science Review) | 122 dB (measured by Audio Science Review) |
| Balanced Output | Yes (XLR line out) | Yes (XLR line out) |
| Inputs | USB, HDMI ARC, optical, coaxial, Bluetooth | USB, optical, coaxial, Bluetooth |
| Outputs | RCA, XLR | RCA, XLR |
| Bluetooth Codecs | SBC, AAC, aptX, aptX HD | SBC, AAC, aptX, aptX HD, LDAC |
| DAC Chip | ES9039Q2M | ES9039Q2M |
| Volume Control | Digital preamp (remote) | - |
| Dimensions | - | 5.9” x 1.7” x 5.1” (150 x 42 x 128.5 mm) |
| Weight | - | 1.6 lbs (710 g) |
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
- SMSL D-6S vs SMSL D200
- SMSL D-6S vs SMSL SU-6
- SMSL D-6S vs Soncoz LA-QXD1
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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The Two Amps and DACs In Full
Fosi Audio ZD3: $179.99 Amazon eBay
Pros: Audio Science Review measured 117 dB SINAD, so its noise and distortion are transparent. It has unusually broad connectivity, with USB, HDMI ARC from a TV, optical, coaxial and aptX HD Bluetooth inputs, plus RCA and XLR outputs and a remote controlled digital preamp for driving powered speakers directly. It matches the rating of the SMSL D-6S for a bit less.
Cons: Its SINAD is a few dB behind similarly rated DACs like the SMSL D-6S, though both are transparent. Bluetooth lacks LDAC, which the SMSL D-6S includes.
Full Fosi Audio ZD3 review and specifications →
| Released | Sep 2024 (2 years ago) |
|---|---|
| Balanced Output | Yes (XLR line out) |
| Bluetooth Codecs | SBC, AAC, aptX, aptX HD |
| DAC Chip | ES9039Q2M |
| Device Type | DAC |
| Inputs | USB, HDMI ARC, optical, coaxial, Bluetooth |
| Outputs | RCA, XLR |
| SINAD | 117 dB (measured by Audio Science Review) |
| Volume Control | Digital preamp (remote) |
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons
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