Fosi Audio is a fast-growing brand from Shenzhen China and has established a strong following within the demanding audio community thanks to its engagement with consumers on the various social platforms, forum websites as well as extensive outreach to content creators and reviewers to talk about their products. They have shown great hunger in wanting to create products that meets the consumers’ needs.

As a frequent Taobao shopper, I have come across the “Fosi Audio” brand when browsing for audio products. So when they reached out to me to share about their upcoming crowdfunding product, I agreed to try out. The new Fosi Audio K7 is a DAC headphone amplifier, and its crowdfunding campaign is open now starting from HKD 1099 (30% off). As this is a pre-launch unit, the product behaviour may be different from the final production version.

When assessing lesser-known brands, I will study their internal components and past reviews to understand how reliable their products were. For such brands, word-of-mouth and user reviews are paramount because these are the real voices that help cement the brand trustworthiness. Fosi Audio K7 uses top-tier quality chipsets from Japan like AK4493SEQ D/A converter, NJW72315 volume control, NJW1119A tone control IC, OPA1612 opamp , TPA6120A2 headphones amp, XMOS XU208 USB interface, QCC3031 Bluetooth chipset. It supports digital USB input, Optical-In, Coaxial input, Bluetooth input, mic input. There are outputs for 4.4mm balanced headphone (rated 2.1W at 32ohms per channel, THD+N < 0.0002%), 3.5mm single-ended (600mW at 32 ohms per channel, THD+N < 0.0005%), and RCA. They deliver an outstanding dynamic range of 121 dB.

The chassis is made of aluminium alloy with two large knobs and several dedicated buttons for easy change of settings like input source, output source, EQ effects, tone adjustment. The knobs can also be pressed to switch settings like headphone gain, Treble-Bass tone levels, mic mute. Due to the aluminium body construction, Fosi Audio designed an external antenna for Bluetooth radio transmission.

The mic only works in USB Audio Class UAC 1.0, and the audio sample rate is fixed at PCM 16-bit 48kHz. Briefly press the power button to toggle. In UAC 1.0, you will see options to adjust mic level, and in Windows/Mac, you will also see mic input. UAC 2.0 disables microphone and extends the audio sample rate to PCM 32-bit 384kHz and DSD256.
The LCD in between the two knobs provide information about the settings. The layouts put emphasis on the sample rate and the input, while the other settings are reflected in small icons. I like the orange LCD which is in line with the colour accents found in all Fosi Audio products.

There are many things I like about the K7. I like the use of orange as the primary colour for design accents, as the colour is easily visible in low-lit environment. I like the compact design, the buttons and knobs look professional and feels high quality. The power button is easily accessible and easy to switch on. The volume control is very responsive so I can adjust audio levels quickly. Connection to Bluetooth is very fast, supporting aptX HD that audiophiles will like, and aptX LL that will satisfy gamers. Finally the product name is printed in small size to avoid drawing too much attention.

Few things that can be improved: I would hope to have a volume mute function, the microphone volume adjustment only has 10 levels and I do not hear much difference in the amplification. The LCD panel could be larger so that I can see the settings more clearly. Finally, the mic input is rather elementary compared to the audio section which boasts balanced output, ultra-high resolution. So, to make it a better DAC for gaming, Fosi Audio should consider throwing in more features to support a wide range of microphones, including XLR, phantom power, and even USB mics.
Audio Quality and Comparison
The Fosi Audio K7 is powerful enough to drive high-impedance headphones like the Sennheiser HD 800S to achieve the headphones potential, producing fine details over a wide dynamic range. The music is coherently presented across the frequency range without excessive colour that changes the character of the headphones. I find that the bass is slightly enhanced to give some musical emphasis, and the richness extends to the midrange while not causing excessive cloud. The treble seems to maintain neutrality so you won’t get that hyper-airy feel. I would think the K7 pairs better with headphones that has emphasis on the upper frequencies, so that the listener can enjoy an overall warm sound signature with an uplift in the treble without too bright.
When I compared the K7 to the Creative Sound Blaster X5, the X5 is better in expressing the treble range, sounding more forward and detailed. The K7 may not have as much push in the upper frequencies, but it compensates with little more open sound staging, the instruments a little more layered and more spatial, so the clarity and sparkle is not lost. The K7 sounds relatively more warm yet disciplined, the Creative X5 feels more detailed. The X5 definitely works better for music that brings out clarity and musical articulation, and the Fosi Audio K7 is more relaxed while offering analytical musical layering.

Apart from comparing audio quality, the K7 and X5 differs in size and features. The Creative X5 has more features, more input and output connections, is USB-powered, comes with software for more setting controls. Operation-wise, the Fosi Audio K7 is easier to operate, more reliable, occupies smaller space, and supports higher quality Bluetooth apt-X HD codec.
Verdict
As a first timer trying out Fosi Audio products, I am impressed with the design, quality components, and operational reliability of the Fosi Audio K7 DAC. This new model delivers a major upgrade in functions and design over its predecessor K5 Pro. Though designated as a Gaming DAC, it works brilliantly as an audiophile DAC to deliver ultra high resolution music tracks.
Thanks to Fosi Audio for sending over this review unit before the crowdfunding launch. I am happy to recommend the K7 if the product specs fits your usage needs, as the features are robust and work great for discerning audio lovers.
Official product page: Fosi Audio K7 Gaming DAC Headphone Amp
Kickstarter page: Fosi Audio K7 Gaming Headphone Amp/DAC by Fosi Audio — Kickstarter
This is not a paid review, and I am writing this article because it is an obligation to share my experience, but it is definitely not required of me to promote this product positively. My purpose of writing reviews is to contribute to smart consumers doing research on this product. Please leave a comment for any questions, recommendations or suggestions.




