FiiO K9 PRO Desktop DAC/Amp (Apos Certified)

$722.50 $849.99

Request A Price Match

This is an Apos Certified product. That means it's refurbished, like new, eligible for our 45-day return policy, carries an Apos Certified One-Year Warranty, and ships from our US facility. Currently, Apos Certified products are only available to customers with a US shipping address. We appreciate your understanding as we aspire to expand our offerings to a broader audience in the future.

FiiO flagship with a collector’s chip 

The FiiO K9 Pro is FiiO’s 2021 flagship DAC/Amp. Featuring a legendary DAC chip and an utterly elegant body, this is a desktop combo that sounds even better than it looks.

Collector’s AKM AK4499 DAC chip 

The K9 Pro uses a legendary AKM AK4499 DAC chip, renowned in the audio industry for its exceptional performance. It supports up to 384kHz and native DSD256 audio.

Exemplary THX AAA Amp

The THX AAA 788+ chip used in the K9 Pro provides exemplary details and dynamics for both low and high-impedance headphones. The K9 Pro can output up to 46Vpp transients when driving high-impedance loads, and up to an undistorted 2W when pushing low-impedance loads. Compared to the original, the output power of the K9 Pro has increased by more than 50% with higher heat dissipation efficiency.

Dual femtosecond clocks

Using an ultra-precise clock management system, the K9 Pro can maintain maximum quality no matter the source. Dual asynchronous femtosecond clocks are used to decode USB and Bluetooth sources, while automatic PLL clocks are used to decode optical and coaxial sources.

Hi-res Bluetooth

The K9 Pro employs the Qualcomm QC5124 to handle Bluetooth duties, with support for formats such as LDAC, aptX HD and aptX Adaptive. This chip ensures that Bluetooth connections are both reliable and quick, satisfying both the low latency needs for games/videos and the high bitrate necessary for high resolution audio.

Flawless volume adjustment 

The volume knob may seem like a pretty simple component of an amp, but executing it well is crucial to the listening experience. The ADC curve reconstruction method of volume adjustment used in the K9 Pro effectively minimizes any left-right channel volume imbalance and noise. It also results in a smooth change of volume across all levels.

3-way gain adjustment

Switch between low, medium, and high gain to accommodate your entire headphone library. Thanks to a pure hardware gain circuit, the K9 Pro maintains the dynamic range and fidelity of your music even while amplifying high-sensitivity headphones at low gain.

Utterly elegant UI

Controls are clearly and intuitively laid out for an effortless experience. Metal switches are used for controlling input selection and gain level.

Light it up

The RGB indicator lights surrounding the stainless steel volume knob change colors depending on the currently playing sample rate.

Take control

Built-in Bluetooth low energy technology allows you to use the FiiO Control App to control functions like channel balance, sleep timer at any time, even when not in Bluetooth mode.

Product highlights 

  • Collector’s AKM AK4499 DAC chip
  • THX-AAA 788+ tech
  • Dual femtosecond clocks
  • Qualcomm QCC5124
  • Supports LDAC, aptX adaptive, aptX HD
  • App control
  • Truly balanced design
  • Dual voltage linear transformer
  • Wide connector selection
  • Lossless MQA decoding
  • Bluetooth format indicator


  • DAC chip: AKM AK4499
  • USB chip: XMOS XUF208
  • Bluetooth chip: Qualcomm QCC5124
  • Amp: THX-AAA 788+
  • Gain: L/M/H
  • Supported Bluetooth codecs: AAC, SBC, aptX, aptX LL, atpX HD, LDAC, aptX adaptive
  • Maximum supported sampling rates
    • USB DAC: 32-bit/384kHz, DSD256
    • Coaxial: 24-bit/192kHz
    • Optical: 24-bit/96kHz
  • Recommended headphone impedance: 16-600Ω
  • USB: Type-C, USB B (data transmission)
  • Inputs: RCA, 4.4mm balanced, optical
  • Outputs: 4.4mm balanced, XLR, 6.35mm, RCA
  • Weight: 6lbs (2750g)

Single-ended lineout parameters

  • THD+N: 0.0007%
  • SNR: ≥123dB
  • Crosstalk: ≥110dB
  • Noise floor: <1.9uV
  • Frequency response: 20Hz - 20kHz
  • Line level: 2.5Vrms

Balanced line out performance parameters:

  • THD+N: 0.0004%
  • SNR: ≥128dB
  • Crosstalk: ≥123dB
  • Noise floor: <1.9uV
  • Frequency response: 20Hz - 20kHz
  • Line level: 5Vrms

Single-ended headphone output parameters:

  • Continuous undistorted output power 1: ≥1.1W (16Ω/ THD+N< 1%, Aux in)
  • Continuous undistorted output power 2: ≥2W (32Ω/THD+N< 1%, Aux in)
  • Continuous undistorted output power 3 : ≥278mW (300Ω/ THD+N< 1%, Aux in)
  • Output impedance: <1Ω
  • Crosstalk: ≥75dB
  • THD+N: <0.0005%
  • Noise floor: <2uV
  • SNR: ≥123dB
  • Frequency response: 20Hz - 20kHz
  • Max output voltage: >26Vp-p

Balanced headphone output parameters

  • Continuous undistorted output power: ≥1.1W
  • Output impedance: <1Ω
  • Continuous undistorted output power 2: ≥W (32Ω / THD+N < 1%, Aux in)
  • Continuous undistorted power 3: ≥1.1W (300Ω/ THD+N <1%, Aux in)
  • Noise floor: <3uV
  • Frequency response: 5Hz - 50kHz
  • Output impedance: <1Ω
  • Crosstalk: ≥114dB (1kHz, Aux in)
  • THD+N: <0.0004%
  • SNR: ≥123dB
  • Max output voltage: >51Vp-p

What pairs well

Featured reviews

"Incredible....great build quality, great sound quality...absolutely worth the asking price." -Joshua Valour

"My favorite DAC/ all-in-one, no compromise solution." -DMS

"The only DAC/amp you'll ever need." -Home Studio Basics

Professional Product Review of FiiO K9 PRO Desktop DAC/Amp (Apos Certified)

FiiO K9 PRO Desktop DAC/Amp (Apos Certified) User Manual Download

Apos Certified

Recently viewed