FiiO K9 AKM Desktop DAC and Headphone Amplifier with Bluetooth

At a Glance

• Drive power-hungry headphones (desktop USB audio + headphones)
• Connect to home audio setups (desktop USB audio + active speakers)
• USB-C connector (with included USB data cable) for easy connection to USB-C mobile devices
• USB-B connector for interfacing with personal computer
• RCA + XLR-3 balanced line out (for active speakers, monitors, external amplifiers)
• Connect to mobile devices (players, computers)
• Built-in Bluetooth Low Energy (BLE) technology allows you to use the FiiO Control app to control functions like filter selection, EQ, channel balance, and more even when not in Bluetooth mode.

ADM Flagship DAC Combo

The K9 AKM applies AKM's latest flagship DAC combo, AK419EQ + AK4499EX. Based on the newly designed technology of totally separated digital and analog sections, the DAC combo even incorporates the newly developed DWA Routing technology to improve the signal-to-noise ratio and reduce noise, resulting in more realistic, detailed, and natural sound transmission, as if you were there with the performing artists.

High-End Amplifier

The K9 AKM features the THX AAA 788+ amplifier, which provides an extraordinary 1% undistorted power output up to 780mW at 300 ohms and up to 2000mW at 32 ohms. No matter if you use low-impedance or high-impedance headphones, the K9 AKM will drive them with ease.

Precisely Designed

• From DAC, to volume adjustment, to amplification, every part of the K9 AKM is truly balanced for greatly reduced crosstalk and more authentic sound.
• The PCB of the K9 features a partitioned layout, fully separating the major sections of the audio circuit, which guarantees the integrity of the audio signal being processed.
• A six-stage audio circuit was designed to ensure a pure, delicate, yet rich sound. I/V conversion, LPF filter, digital volume adjustment, buffer amplifier, preamplifier, and post-stage drive.

Robust Power Supply

• Electricity is the mother of sound, so special attention was paid to optimizing the K9 AKM's power supply to ensure excellent sound. The linear power supply with its four massive 4700uF capacitors, makes sure that the rest of the system gets abundant clean power, continuously.
• The digital portions of the K9 AKM physically receive power separately from the analog portions, for effective shielding against audio interference between the two circuits. This ensures pure and faithful reproduction of your music.
• Besides the special high-performance linear power supply, the power stabilization and filtering within the audio circuit is also a big contributor to the K9 AKM's excellent sound. Specifically, in each stage of the audio circuit, ultra-low-noise LDOs are employed for voltage regulation.

Precision Clock Management

A dual-mode clock management design is utilized for the K9 AKM. Accurate and stable dual-mode clock management allows the K9 to easily play back high-resolution audio with the greatest fidelity, as if you were there with the performing artists.

Hi-Res Bluetooth

The K9 AKM employs the Qualcomm QCC5124 chip 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.

Compatible with UAC1.0 / UAC2.0

the K9 AKM supports both UaC1.0 and UAC2.0 modes, allowing you to use the K9 AKM with devices that are plug and play or with devices that can work with K9 AKM, with an additional driver for even better compatibility. The FiiO control app allows you to easily switch between UAC1.0 and UAC2.0 modes.

Next-Level Volume Control

Adjusting the volume may look like a simple concept, but a good execution of it is crucial to an excellent audio experience. The ADC curve reconstruction method of volume adjustment used in the K9 AKM effectively minimizes any left-right channel volume imbalance and noise. It also results in a smooth change of volume across 120 levels of volume. This attention paid to the simple process of volume adjustment is just another layer to savor your music with the K9.

Lighting Up the Mood

The RGB indicator lights surrounding the volume knob can light up differently, depending on the currently playing sample rate and Bluetooth format, and give the K9 and its surrounding desk space some fun personality.

Professional PEQ

Through the FiiO Control app, you can quickly switch between seven music tuning style presets on the K9 AKM. If the selected tuning style fits the music you are listening to, you can acquire a more vivid and pleasant experience. If the preset tuning is not to your liking, you can self-define up to three PEQ designs, to finely adjust to your favorite listening style.

Horizontal or Vertical

Featuring all-aluminum construction made from an integrated stretching and CNC process to ensure the body's strength and precise finish, the K9 AKM sits on your surface handsomely in either a horizontal or vertical orientation.

FiiO K9 AKM Specs

Number of Headphone Channels	2-Channel
Recommended Headphone Impedance	8 to 350 Ohms
Headphone Output Power	1/4" Unbalanced: ? 1 W into 16 Ohms (1% THD) ? 1.5 W into 32 Ohms (1% THD) ? 200 mW into 300 Ohms (1% THD) 4.4 mm Balanced: ? 2 W into 32 Ohms (1% THD) ? 1 W into 16 Ohms (1% THD) XLR Balanced: ? 1 W into 16 Ohms (1% THD) ? 2 W into 32 Ohms (1% THD) ? 780 mW into 300 Ohms (1% THD)
Analog Audio I/O	1x 4.4 mm TRRRS Balanced Stereo Line Input 1x Stereo RCA Line Input 1x Stereo RCA Line Output 2x XLR 3-Pin Balanced Mono Line Output (1 Stereo Pair) 1x 4.4 mm TRRRS Balanced Stereo Headphone Output 1x 1/4" TRS Unbalanced Headphone Output 1x XLR 4-Pin Balanced Stereo Headphone Output
Digital Audio I/O	1x TOSLINK Optical S/PDIF Input 1x RCA Coaxial S/PDIF Input
USB I/O	1x USB-B (Digital Input, Update) 1x USB-C
Wireless	Bluetooth 5.1
Frequency Response	RCA Line Outputs: 20 Hz to 50 kHz -3.5 dB XLR Line Outputs: 20 Hz to 50 kHz -3.5 dB 1/4" Headphone Outputs: 20 Hz to 50 kHz -3.5 dB 4.4 mm Balanced Headphone Outputs: 20 Hz to 50 kHz 3.5 dB XLR Balanced Headphone Outputs: 20 Hz to 50 kHz 3.5 dB
Power Requirements	AC Input

Number of Headphone Channels	2-Channel
Recommended Headphone Impedance	8 to 350 Ohms
Headphone Output Power	1/4" Unbalanced: ? 1 W into 16 Ohms (1% THD) ? 1.5 W into 32 Ohms (1% THD) ? 200 mW into 300 Ohms (1% THD) 4.4 mm Balanced: ? 2 W into 32 Ohms (1% THD) ? 1 W into 16 Ohms (1% THD) XLR Balanced: ? 1 W into 16 Ohms (1% THD) ? 2 W into 32 Ohms (1% THD) ? 780 mW into 300 Ohms (1% THD)
Digital Chipset	DAC: 1 x AKM AD4499EX AKM AK4191EQ USB: 2 x XMOS XMOS XUF 208 Bluetooth: Qualcomm QCC5124
Analog Circuitry	Volume IC: 2x NJU72315 Power Amplifier Op-Amp: 2x THX AAA 788+ Low-Pass Filter Op-Amp: 2x OPA1612
EQ	No
Display	No

Analog Audio I/O	1x 4.4 mm TRRRS Balanced Stereo Line Input 1x Stereo RCA Line Input 1x Stereo RCA Line Output 2x XLR 3-Pin Balanced Mono Line Output (1 Stereo Pair) 1x 4.4 mm TRRRS Balanced Stereo Headphone Output 1x 1/4" TRS Unbalanced Headphone Output 1x XLR 4-Pin Balanced Stereo Headphone Output
Digital Audio I/O	1x TOSLINK Optical S/PDIF Input 1x RCA Coaxial S/PDIF Input
USB I/O	1x USB-B (Digital Input, Update) 1x USB-C
Other I/O	1x SMA Coaxial Antenna
Wireless	Bluetooth 5.1
Bluetooth	5.1
Supported Audio Codecs	AAC, aptX, aptX Adaptive, aptX HD, aptX LL, LDAC, SBC

Frequency Response	RCA Line Outputs: 20 Hz to 50 kHz -3.5 dB XLR Line Outputs: 20 Hz to 50 kHz -3.5 dB 1/4" Headphone Outputs: 20 Hz to 50 kHz -3.5 dB 4.4 mm Balanced Headphone Outputs: 20 Hz to 50 kHz 3.5 dB XLR Balanced Headphone Outputs: 20 Hz to 50 kHz 3.5 dB
Maximum Output Level	RCA Line: 2.3 Vrms (At 1 kHz, 10 Kilohms) XLR Line: 4.7 Vrms (At 1 kHz, 10 Kilohms) 1/4" Headphone Outputs: 21 V p-p 4.4 mm Balanced Headphone Outputs: 42 V p-p XLR Balanced Headphone Outputs: 42 V p-p
Impedance	Headphone/Balanced Headphone Outputs: < 1 Ohm (32-Ohm Load)
THD+N	RCA Line: < 0.00027% (1 kHz /-0.7 dB at 10 Kilohms) XLR Line: < 0.0002% (1 kHz /-0.7 dB at 10 Kilohms) 4.4 mm Line: < 0.00029% (1 kHz / -9.5 dB at 32 Ohms) 1/4" Headphone: < 0.00026% (1 kHz / -1.3 dB at 32 Ohms) 4.4 mm Balanced Headphone: < 0.00029% (1 kHz / -9.5 dB at 32 Ohms) XLR Balanced Headphone: < 0.00029% (1 kHz / -9.5 dB at 32 Ohms)
SNR	RCA Line: ? 119 dBA XLR Line: ? 128 dBA 4.4 mm Line: ? 124 dBA 1/4" Headphone: ? 127 dBA 4.4 mm Balanced Headphone: ? 124 dBA XLR Balanced Headphone: ? 124 dBA
Noise	RCA Line Outputs: < 2.9 µV (A-Weighted) XLR Line Outputs: < 1.9 µV (A-Weighted) 1/4" Headphone: < 3 µV (A-Weighted) 4.4 mm Balanced Headphone: < 5.2 µV (A-Weighted, Aux In) XLR Balanced Headphone: < 5.2 µV (A-Weighted, Aux In)
Crosstalk	RCA Line Outputs: ? 112 dB (1 kHz, 10-Kilohm Load) XLR Line Outputs: ? 122 dB (1 kHz, 10-Kilohm Load) 1/4" Headphone: ? 76 dB (1 kHz, 32-Ohm Load) 4.4 mm Balanced Headphone: ? 116 dB (1 kHz, 32-Ohm Load) XLR Balanced Headphone: ? 116 dB (1 kHz, 32-Ohm Load)

Sample Rates	USB-A Input: 768 kHz (PCM) Optical S/PDIF Input: 96 kHz (PCM) Coaxial S/PDIF Input: Up to 192 kHz (PCM)
Bit Depths	Up to 32-Bit (PCM)

OS Compatibility	Computer: Windows / macOS Mobile: Android/iOS
OS Compatibility	Windows macOS
Mobile App Compatible	Yes: Android & iOS App Name: FiiO Control Functionality: Adjust Settings
Mobile Device Compatibility	No

Power Requirements	AC Input
AC Input Power	User Selectable: 100 to 240 VAC, 50 / 60 Hz
AC/DC Power Adapter	No

Dimensions	8.84 x 7.9 x 2.8" / 22.45 x 20 x 7.2 cm (without Feet)
Weight	5.7 lb / 2.6 kg

Package Weight	8.21 lb
Box Dimensions (LxWxH)	14.3 x 12.6 x 6.9"