Fosi Audio K7 – AK4493S Desktop DAC/AMP, 2100mW Balanced, Bluetooth aptX HD

Fosi Audio K7 – AK4493S Desktop DAC/AMP, 2100mW Balanced, Bluetooth aptX HD

The Fosi Audio K7 is a desktop DAC and headphone amplifier built for the overlap between gaming and serious listening. It runs AKM's AK4493SEQ VELVET SOUND DAC, Texas Instruments' TPA6120A2 amplifier, and Qualcomm's QCC3031 Bluetooth chip — components found in dedicated audiophile hardware — in a compact aluminum chassis that fits under a monitor and works directly with PS5, Switch, and PC without drivers or configuration.

Chipset Architecture

The AK4493SEQ is AKM's current flagship stereo DAC, capable of PCM decoding to 384kHz/32bit and DSD256 via USB, with 123dB dynamic range and 0.00007% THD+N at the chip level. Upstream, the XMOS XU208 handles USB audio processing — it's been the reliable standard for desktop USB audio for years, ensuring stable high-res transmission and clean USB-to-audio handoff.

The amplifier section uses a dual-mono TPA6120A2 configuration, paired with OPA1612 op-amps for the signal path. The result is 600mW @32Ω single-ended and 2,100mW @32Ω balanced — enough to drive Hifiman planars, Sennheiser HD 800, and everything between without hitting the ceiling. Noise floor measures ≤2.5μV single-ended and ≤6.5μV balanced: no audible hiss on IEMs, no background noise on sensitive headphones.

Balanced Output — What It Actually Means Here

The K7 runs fully balanced circuitry from DAC to headphone output — it's not a split-from-single-ended design. The 4.4mm output delivers ≤0.0002% THD with a dual-mono amp stage. For headphones with detachable cables, using a 4.4mm terminated cable will give you the full balanced signal path, lower crosstalk, and the power headroom that the amp is designed around.

Inputs & Connectivity

Front panel: 3.5mm mic input (adjustable gain, UAC 1.0 mode required), 3.5mm single-ended output, 4.4mm balanced output. Rear panel: USB-C (PCM 384kHz/DSD256), Optical (PCM 384kHz/DSD256), Coaxial (PCM 384kHz/DSD256), Bluetooth 5.0 antenna, RCA outputs. The included 3.5mm headphone splitter converts a 4-pole gaming headset into separate headphone and mic connections — no additional adapter needed for existing gaming setups.

PS5 Pro and PS5 work via USB-C in UAC 1.0 mode (plug-and-play). UAC 2.0 requires the Windows driver and disables microphone input. XMOS firmware is field-upgradeable via USB-C.

Controls & Display

Two large knobs: left for volume (with long-press gain toggle), right for bass/treble/menu navigation. Five shortcut buttons for input switching, bypass, and display control. The 1.5" monochrome LCD shows input source, sample rate, and current settings in real time — you know exactly what the K7 is doing without guessing. Bypass mode flattens the signal path in under two seconds.

Founder's Take

The K7 is marketed as a gaming DAC/AMP — but that label undersells it. This is a device built for gamers that ends up being a definitive solution for audiophiles too. That's what happens when you put an AK4493S, a TPA6120, and 2,100mW of balanced output into a unit under 220€.

For gaming: the neutral, wide soundstage means positional audio in FPS reads correctly — footsteps, directional cues, ambience all land where they should. Hardware bass and treble controls let you tune for immersion or competitive clarity without software or DSP latency. PS5 is plug-and-play via UAC 1.0, mic passthrough included.

The AK VELVET SOUND signature — neutral, clear, non-fatiguing — works equally for gaming sessions and serious listening. At this price, it's the most complete answer to the gamer-audiophile overlap we've put in the catalogue.

Honest note: no LDAC, and mic input requires UAC 1.0 — incompatible with hi-res USB audio simultaneously on PC.

IN THE PACKAGE

• 1× Fosi Audio K7 DAC/AMP
• 1× DC 12V 2A Power Supply
• 1× USB-A/C to USB-C Cable
• 1× Bluetooth Antenna
• 1× 3.5mm Headphone & Mic Splitter
• 1× User Manual