Fiio K9 PRO ESS DAC HEADPHONE AND DAC

You’d think I was reviewing a fictional robotic canine with a name K9 (Doctor Who fans will get this), but this DAC/ headphone amp is anything but imaginary, and comes from the Chinese company Fiio. I personally own an aged X1 and X5 DAP. In the house, I use the X5 line output into a Slee Voyager headphone amp and get a very reasonable sound. I have watched this company grow since its early beginnings in the UK, starting with basic DAPs and headphone amps and now growing into producing some of the best-looking and technological personal products out there. Indeed, looking at the products over the last few years has seen Fiio produce some amazing kit to take on the competition. The K9 Pro ESS is their flagship Hi-Res desktop and comes in at a very good £699.99.

Guangzhou FiiO Electronics Technology Co., Ltd was established in 2007 in Guangzhou City, China, and has moved away from just doing DAPs to cables, amplifiers, and earphones. The name Fiio is made up of “Fi” for fidelity and “io” to represent the digital language of ones and noughts. Clever.

BUILD QUALITY OF Fiio K9 PRO

The K9 Pro ESS is one up from the K9 Pro. It uses two well-respected ESS ES9038 Pro DACs, one per channel, rather than the base model’s AK4499. All in all, the Pro ESS adds up to better THD, SNR, and a slightly greater output level (2100mW into 32 ohm). The body is beautifully presented with gold-edged central volume knob on the front (as opposed to silver on the base model) and vents at the side of the unit with slightly raised ridges along the edges. It looks well thought out. The unit comes with 6 stick-on feet for you to add if you decide to use the unit horizontally, or not if you put the unit on its side on the supplied stand. The unit also comes with a spare fuse.

This is a truly balanced design with a dual voltage linear transformer and supports SBC, AAC, LDAC, aptX Adaptive, and aptX HD Bluetooth codecs, as well as WAV/Flac/DSD/MQA sampling rates. With output connectors (XLR 4pin and 4.4mm balanced plus standard SE ¼” on the front left, the right-hand side has the input selector plus gain (low/