FiiO announces flagship DAC and headphone amplifier with hi-res Bluetooth streaming

FiiO K9 Pro ESS Headphone Amp / DAC
(Image credit: FiiO)

FiiO has launched its flagship DAC and headphone amplifier, the K9 Pro ESS. It's packed with features for hi-res digital audio and a wide variety of headphones, along with an array of connections, offering MQA support and Bluetooth 5.0 streaming

The K9 Pro can handle a wide range of file types, supporting hi-res audio files up to 32-bit/384kHz PCM plus DSD256 and MQA files from high-fidelity services such as Tidal.

There’s a vast selection of audio inputs to choose from, too. The FiiO K9 Pro ESS expands on the choices offered by its more budget stablemate, the K7, providing line level RCA input on the analogue side, and coaxial, optical, USB-B and USB-C inputs on the digital side. There’s also compatibility for external devices thanks to line level and XLR outputs, while headphone users can plug their cans into the 6.35mm single-ended, 4.4mm balanced or 4-pin balanced XLR headphone connections.

As a DAC and headphone amplifier, the FiiO K9 Pro ESS should be a dab hand at driving all kinds of headphones as well as promising enhanced audio quality. FiiO’s latest provides dual THX AAA788+ amplification, which it claims can “effortlessly” power headphones with a wide impedance range of 16 - 600 ohms. You can also manually select low, medium and high gain levels to adjust for your headphones’ own impedances or sensitivities.

FiiO K9 Pro ESS headphone amp/DAC

(Image credit: FiiO)

Bluetooth 5.0, meanwhile, allows for pairing of devices such as smartphones, portable music players and PCs, and even supports streaming for hi-res wireless codecs including aptX HD, aptX Adaptive, and LDAC.

The K9’s twin ES9038 Pro DACs promise to deliver “an impressively musical, detailed, and expressive sound, whatever the source.” Timing shouldn’t be a problem, either, thanks to the dual-clock management of the model’s XMOS XUF208 decoding chip, promising “incredibly accurate handling of all digital audio files”.

That isn’t the end of it. Audio output from the K9 Pro has been carefully handled by the company’s engineers with a “partitioned layout” of the circuit board. What this means, they claim, is that not only is the power supply kept separate from the audio signals, but analogue and digital audio are separated from each other to ensure each signal’s integrity. Audio signals coming from the right and left channels are also processed separately by the unit in an effort to reduce crosstalk and preserve high-quality audio fidelity.

Weighing around 2.75kg, the FiiO K9 Pro ESS is available now for £699 / $859 / AU$1349. It also comes as standard with its own Bluetooth antenna, USB-B to USB-A cable, 3.6mm to 6.35mm adapter and a vertical stand for placement. 


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Harry McKerrell
Staff writer

Harry McKerrell is a staff writer at What Hi-Fi?. He studied law and history at university before working as a freelance journalist covering TV and gaming for numerous platforms both online and in print. When not at work he can be found playing hockey, practising the piano or forcing himself to go long-distance running.