Fosi Audio S3: Compact Streamer, DAC & Preamp with HDMI eARC and Roon Ready

Fosi Audio is clearly aiming at a sweet spot with the new S3—a compact, all-in-one streaming solution that doesn’t just tick boxes, but actually solves a real-world problem: how to build a clean, modern hi-fi system without stacking boxes.

At its core, the S3 combines a network streamer, DAC, and preamplifier into a single, understated chassis. That means you can run it straight into a power amp or a pair of active speakers and call it a day. No clutter, no unnecessary complexity—just a streamlined signal path built for how people actually listen today.

Small box, serious signal chain

Under the hood, Fosi hasn’t cut corners. The S3 is built around the well-regarded AKM4493SEQ DAC, capable of handling PCM up to 32-bit/384 kHz. The analog stage uses OPA1612 op-amps in a fully balanced circuit, with ELNA capacitors and a low-noise LDO power supply keeping everything clean and stable.

The Fosi Audio S3 is a network audio streamer with a built-in DAC and preamplifier, designed for home audio systems and music streaming.

It’s a thoughtful design—separating digital and analog sections to minimize interference, and offering proper XLR outputs for those running balanced setups. In other words, this isn’t just “feature-rich”—it’s properly engineered.

Streaming without limitations

Where the S3 really starts to shine is on the streaming side. Pretty much everything is covered: AirPlay 2, Spotify Connect, TIDAL Connect, Google Cast, DLNA, and even Roon Ready support. Whether your music lives on a NAS, in the cloud, or on your phone, the S3 plugs straight into your ecosystem without friction.

Control happens through Fosi’s own app, which includes playback management and a built-in 5-band EQ for those who like to fine-tune their sound.

Connectivity is equally flexible, with dual-band Wi-Fi, Ethernet, and Bluetooth 5.3 onboard. It’s the kind of versatility that makes the S3 feel less like a component—and more like the central brain of a modern system.

The Fosi Audio S3 features dual-band Wi-Fi, Bluetooth 5.3, and Ethernet, supports 12V trigger synchronization, and features overload protection. Its compact design allows it to be used as a network source in a desktop or home audio system.

Not just for music

Interestingly, Fosi is also leaning into the idea that hi-fi systems shouldn’t live in isolation. The inclusion of HDMI eARC means you can hook the S3 directly to your TV and use your stereo setup for film and series audio—no AV receiver required.

There’s even a dedicated subwoofer output, making it easy to build a compact but capable 2.1 system.

Designed for real-world systems

With its compact footprint and clean layout, the S3 fits just as naturally on a desktop as it does in a living room rack. Add 12V trigger support and protection circuits, and it’s clear Fosi is thinking about integration—not just specs.

Fosi Audio S3 – Key Specifications

• DAC: AKM4493SEQ
• Streaming: AirPlay 2, Spotify Connect, TIDAL Connect, Google Cast, DLNA, Roon Ready
• Max resolution: up to 32-bit / 384 kHz (Roon)
• Outputs: Balanced XLR, subwoofer out
• Connectivity: Wi-Fi (2.4/5 GHz), Ethernet, Bluetooth 5.3
• HDMI: eARC (PCM up to 24-bit / 192 kHz)
• Power: 12V DC
• Dimensions: 17.3 × 17.3 × 4.7 cm