Fosi Audio ZH3: Your All-in-One Desktop HiFi DAC/Headphone Amp/Preamp

Every serious audiophile wants clarity, power, and flexibility in their setup — without turning their desk into a jumbled mess of gear. Enter the Fosi Audio ZH3: a fully balanced DAC, headphone amplifier, and preamp all in one sleek, desktop-friendly unit. Whether you’re growing your HiFi rig, powering high-end headphones, or switching between speakers and headphones, the ZH3 is built to deliver.

Design & User Experience

The moment you see the ZH3, you notice its premium build. It inherits the signature aesthetics of Fosi’s Z-series: an all-black aluminum body and refined matte finish that feels solid in hand and looks clean in any room. Up front, the bright orange multi-function knob isn’t just for show — it controls volume, lets you select inputs, and access settings. Accompanying it are a 1.5-inch LCD display that shows volume and input status, and two headphone outputs: a 6.35mm single-ended jack plus a 4.4mm balanced output.

On the rear, the ZH3 stays just as versatile. You’ll find XLR and RCA outputs for sending signal to power amps or active speakers, plus multiple digital and analog inputs: USB, optical, coaxial, and RCA. A DC 12V power input keeps the whole unit compact and neat. Also included are 12V Trigger In/Out jacks so the ZH3 can integrate with other Z-series gear (like ZD3 or ZA3), letting you power multiple components on/off together.

Inside the ZH3: Chips & Circuitry

What really elevates the ZH3 is what’s inside. At its heart:

• AKM 4493SEQ DAC — supports high-res audio decoding

• XMOS XU316 USB processor — ensures reliable, high-quality digital input

• Four OPA1612 op-amps for clean, dynamic amplification

Together, they support up to PCM 768 kHz / 32-bit and DSD512, which means virtually any audio source you throw at it is handled with precision.

The ZH3’s fully balanced complementary push-pull architecture delivers strong performance. In a 32Ω load, it pushes up to 2.5 W per channel, a figure that gives you headroom even with demanding headphones. Channel separation is extremely good (≈117 dB), meaning vocals and instruments stay separated and precise.

In the signal path, Fosi went with high precision parts: 0.1% resistors, low-drift capacitors, and ultra-low noise regulators. Eleven ultra-low-noise LDOs coupled with solid-state capacitors help keep the background noise floor very low (≤ 1.9 µV). Even when running at high gain, the ZH3 stays whisper-quiet.

Key Specifications

• DAC Chip: AKM 4493SEQ

• USB Processor: XMOS XU316

• Op-Amps: 4 × OPA1612

• Supported Formats: PCM up to 768 kHz / 32-bit, DSD512

• Output Power: Up to 2.5 W @ 32 Ω per channel

• SINAD: ≥115 dB

• SNR: ≥121 dB

• THD+N: ≤0.00018%

• Noise Floor: ≤1.9 µV

Features & Flexibility

Besides power and clean circuitry, the ZH3 is built for flexibility:

• Bypass mode – Skip all tone, filter, or EQ circuits to preserve signal purity when feeding external amps.

• UAC mode switching – UAC 1.0 for consoles (PS5, Switch) and UAC 2.0 for computers/mobile, maximizing compatibility.

• Output switching – A double-press of the orange knob switches between headphones and active speakers for seamless transitions.

• Volume memory – Remembers your volume settings per output, so when you switch between headphones and speakers you don’t get a sudden jump in volume.

Practical Applications

Here’s how the ZH3 shines in practice:

Headphone Amplifier:
Plug in demanding over-ear headphones (e.g. planar magnetic) into the 4.4mm balanced output. With high output power, clean channel separation, and ultra-low noise, the ZH3 gives you rich, detailed sound with no hiss — great even for sensitive ears.

Preamp Driving Speakers or Power Amp:
If you use passive speakers or have a power amp in your chain, the XLR or RCA outputs let the ZH3 function as your central preamp. From your DAC or source device → ZH3 → power amp or active speakers; the signal stays clean and flexible.

DAC Front End:
Want to use external or tube amps? Use ZH3 purely as a DAC feeding analog gear. You still get the benefits of its high-res decoding, low noise, and refined output stage.

Desktop Switch Hub:
For desktops especially, switching between headphones and speakers can be tedious. ZH3 simplifies this: double-press the knob to toggle outputs, and everything works without unplugging. Also, set it to auto power off when no signal is detected, saving energy and reducing wear.

Why It Stands Out

What puts the ZH3 ahead of many similar units is how well it balances raw technical capability with real-world usability. Many DAC/amps deliver great specs but skimp on ergonomic detail. ZH3 addresses that:

• It remembers volume levels per output so you aren’t jolted by loud volume shifts.

• It offers solid compatibility for both digital and analog sources, including gaming consoles.

• The finish and build reduce electromagnetic interference and mechanical noise, contributing both to durability and sound purity.

• Its balanced output gives you much lower noise and better channel separation than many single-ended units in this class.

If you’re building a desktop setup, pursuing cleaner sound, or want a single unit that can grow with your system, the Fosi Audio ZH3 offers a compelling package. You get:

• High-res DAC functionality (PCM 768 kHz / DSD512)

• Fully balanced, high-power amplification

• Multiple input/output types

• Intelligent features like bypass, UAC mode switching, and output switching

All packed in a compact, beautifully finished, aluminum body with a user-friendly interface.

For anyone serious about audio — whether headphones, speakers, or just wanting high fidelity — the ZH3 is a standout choice. It’s not just about volume or looks; it’s about quality, control, and clarity.