In the ever-expanding universe of hi-fi audio, the pursuit of exceptional sound quality often leads enthusiasts down paths filled with complexity, high costs, and intimidating setups. However, every so often, a brand emerges that manages to defy these expectations by making high-quality audio remarkably accessible.

Enter Fosi Audio, a company dedicated to providing audiophiles, music lovers, and newcomers alike with powerful yet compact amplifiers, DACs, and audio solutions that promise outstanding performance without breaking the bank.

Fosi Audio has swiftly garnered attention for its ability to combine sleek, minimalist designs with robust engineering, offering products that easily integrate into both seasoned audiophile setups and beginner-friendly environments. Whether you’re looking to elevate your desktop listening experience or enhance your home stereo system, Fosi Audio positions itself as a game-changer, challenging traditional perceptions about the cost and complexity required for exceptional sound.

In this review I will have a look at the new Fosi Audio K7

The Fosi Audio K7 is positioned as a “gaming headphone amp & DAC,” targeting audiophiles and serious gamers who value high-quality audio. Specifically for gamers, the K7 includes a microphone input with built-in noise cancellation, ideal for clear communication during online gaming sessions.

The K7 stands out as an appealing device because it combines a high-quality headphone amplifier and DAC with excellent operational features, and there is even a very nice informative LCD screen

The K7 offers four digital inputs:
– Coaxial
– Optical
– Bluetooth
– USB-C (The K7 supports UAC 1.0 and high-resolution UAC 2.0 audio)

Outputs:
– RCA Analogue, to connect to an external amp or active speakers.

The unit includes volume control, adjustable treble and bass controls (which can be bypassed)

Two headphone output, single ended 3.5 mm and a balanced 4.4 mm jack. By pressing the left volume knob you can switch between low and high gain. And left from the headphone ports a microphone input.

From a technical standpoint, the DAC is equipped with the AKM4493SEQ chip, known for handling PCM audio signals up to 384kHz/32bit and DSD256 via USB, while coaxial and optical inputs support resolutions up to 24bit/192kHz. 

Bluetooth connectivity is managed by the Qualcomm QCC3031 chip, which provides lossless audio streaming at 24bit/48kHz and supports aptX HD, aptX LL, aptX, AAC, and SBC codecs.

The  amplifier circuit employs dual chips OPA1612 and TPA6120 enabling effective driving of headphones with impedance ratings from 16Ω up to 300Ω. 

The unbalanced 3.5mm headphone output delivers 600mW+600mW at 32Ω (with THD+N <1%), the balanced 4.4mm output increases this significantly to 2100mW+2100mW at the same impedance and distortion rating.

 The unit is powered via an external power supply rated at 12V 2A

What’s in the box

My test equipment:
– Fir Audio M5
– Arya Stealth
– Eversolo DMP-A8
– MacBook Pro 2024
– Playstation 5

Tested Albums:
– Stacey Kent – Summer me, Winter me
– Robin Mckelle – Alterations
– Terell Stafford – Brotherlee love
– Catherine Russel – Strictly Romancing
– Chris Minh Doky/Larry Goldings – Scenes from a Dream

Sound Quality

The sonic presentation of the K7 is impressively transparent and balanced, faithfully reproducing the entire audible spectrum without coloration. It offers genuine neutrality, conveying exactly what’s present in the source material. Across various scenarios, music playback, gaming sessions, or teams meetings, the audio remains effortlessly smooth and articulate.  Enough power for planar headphones yet sensitive IEM’s exhibit no audible noise, hiss, or distortion, resulting in an exceptionally pure listening experience. 

Treble

High-frequency performance on the K7 is articulate and refined, revealing fine detail and excellent definition. The integrated tone controls offer adjustments smoothly. Treble changes are subtle yet effective. This design makes it straightforward to enhance brightness or tame overly sharp recordings gently. Gamers, particularly those requiring precise micro details, will find these detailed adjustments beneficial.

Bass 

Bass reproduction on the K7 is tight and dynamic, delivering fast performance without overwhelming the listener. It has depth and punch, enriching music and enhancing immersion in games. Adjustments are here just as gradual, meaning you won’t experience abrupt tonal changes. This thoughtful implementation allows users to finely calibrate warmth and impact without any loss in clarity.

Bluetooth 

The pairing process is fast and effortless, and once connected, the device maintains a stable, uninterrupted signal, even a few meters away from the device. Audio quality via Bluetooth is impressively clear. It is no secret I am not a fan of bluetooth audio, but this exceeded my expectations. It is a shame LDAC is not supported though.

Conclusion

The synergy between the AK4493S DAC chip and the TPA6120/OPA1612 amplifier is impressive. Immediately noticeable was the spatial precision compared to similar units I’ve heared before, especially in this price range!

The overall sound signature strikes a compelling balance, revealing but not too analytical, enriched with a pleasing touch of warmth. Its remarkable coherence ensures a pleasant listening experience, and should you prefer a different sonic flavor, subtle tone adjustments provide ample flexibility. I liked the bypass mode the most though, altough the difference between bypass mode was almost none existent (which is a 

Last but not least, the device also fits perfectly in my day to day use, in my working day at home with a lot of teams meetings, muting was faster than a mouse click.