Fosi Audio
Fosi Audio SK02 DAC Amp Headphone Amplifier Desktop USB C to AUX Digital to Analog Audio Converter Adapter Preamp Optical to 3.5mm 4.4mm Balanced Combo for Home Audio System
Bottom line: The Fosi Audio SK02 DAC Amp Headphone Amplifier Desktop USB C to AUX ($79.99 on Amazon as of 2026-10-06): ESS SABRE ES9038Q2M DAC, 120dB SNR, 0.001% THD, 3.7uV noise floor; main trade-off: 300 ohm ceiling stops short of the hardest-to-drive planar cans.
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*Price sourced from Amazon.com. Last updated 2026-10-06. Price and availability subject to change.
Pros & Cons
Pros
- ✓ ESS SABRE ES9038Q2M DAC, 120dB SNR, 0.001% THD, 3.7uV noise floor
- ✓ 4.4mm balanced output pushes 1100mW into 32 ohms
- ✓ Drives IEMs and headphones across a 16-300 ohm range
- ✓ Decodes DSD256 and PCM up to 32bit/384kHz, driver-free plug-and-play
- ✓ CNC single-piece aluminum chassis; USB-C and optical inputs, doubles as preamp
Cons
- ✗ 300 ohm ceiling stops short of the hardest-to-drive planar cans
- ✗ No coaxial or Bluetooth input; only USB-C and optical
- ✗ No RCA line output, so preamp duty runs via 3.5mm/4.4mm only
- ✗ One multifunction knob plus mode buttons has a small learning curve
SpecPicks Verdict
SpecPicks scored Fosi Audio SK02 DAC Amp Headphone Amplifier Desktop USB C to AUX… using a rating × review-volume × price-fit model applied to published specs and reviews across the audio & midi category. Fosi Audio's audio & midi lineup sits within the broader category mid-tier; price and specs are the deciding factors over brand loyalty here. Judge it on the specification table and the price rather than on sentiment: check the figures that decide your use case, then put it side-by-side with two or three close alternatives in the Compare tool before clicking through.
Common buyer scenarios for audio & midi of this kind: matching it to an existing build, replacing a failing part, or upgrading from a previous-generation equivalent. Check the spec table below against your current setup — particularly socket / form-factor / power-rating fields — and confirm compatibility on the retailer's listing before purchase. Prices and stock are set by the retailer and may have moved since this page was last updated.
Key Features
- Compact Yet Powerful: The SK02 employs a minimalist and stylish design language. Despite its small size, it boasts mighty features. It supports DSD256 and PCM 32bit/384kHz high-resolution decoding, along with 3.5mm single-ended and 4.4mm balanced headphone outputs. Its robust power can easily drive wide range of headphones and IEMs with an impedance range of 16-300 ohms
- Stunning Performance: It features a high-end ESS SABRE ES9038Q2M DAC and SGM8262 op-amps. Its excellent circuit design ensures superior parameters with a SNR as high as 120dB, a low noise floor of only 3.7μV, and an incredibly low THD of 0.001%. The 4.4mm balanced output power reaches an impressive 1100mW at 32 ohms. The exceptional high-resolution capability and pure sound quality make every listening experience an extraordinary sensory journey
- User-Friendly Design: The SK02 requires no drivers and offers plug-and-play convenience. It integrates a big multi-functional control knob, allowing easy access to power on/off, play/pause, and volume adjustments. The unit features quick-switch buttons for high/low gain and input modes. Additionally, its colorful indicator lights enable effortless identification of the current working mode and the song's sampling rate
- Remarkable Versatility: Supports USB and optical input, widely applicable for decoding with computers, laptops, CD players, TVs, and projectors. Not only can it function as a headphone amplifier, but it can also serve as a preamp, pairing with active speakers or an amplifier like Fosi Audio V3, ZA3, TB10D amp and passive speakers to form a desktop listening or home audio system
- Exquisite and Durable: The SK02 is crafted from a single piece of aluminum alloy using CNC machining and a delicate sandblasting process. This not only gives it an exquisite appearance but also ensures lasting durability
Full Specifications
| Brand | Fosi Audio |
|---|---|
| Model | SK02 |
| Interface | 3.5mm, 4.4mm, Optical, USB |
| Unit Count | 1.0 Count |
| Part Number | SK02 |
| Connectivity | USB-C |
| Compatibility | Switch |
| Material Type | Aluminum Alloy |
| Mounting Type | Tabletop/Desktop |
| Interface Type | 3.5mm, 4.4mm, Optical, USB |
| Number of Pins | 11 |
| Audio Output Mode | Single-Ended, Balanced |
| Compatible Devices | Laptop, Computer, CD player, TV, Projector |
| Number of Channels | 2 |
| Warranty Description | 24 Month Manufacturer |
| Smart Home Compatibility | Not Smart Home Compatible |
Ready to buy?
Fosi Audio SK02 DAC Amp Headphone Amplifier Desktop USB C to AUX Digital to Analog Audio Converter Adapter Preamp Optical to 3.5mm 4.4mm Balanced Combo for Home Audio System is listed on Amazon. Price, availability, shipping and returns are set by Amazon and its sellers — check the listing for current terms. SpecPicks earns a small commission on qualifying purchases — thank you for supporting independent review work.
*Price sourced from Amazon.com. Last updated 2026-10-06. Price and availability subject to change.
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