General Specifications
Name/Model K11 R2R Hardware solution SoC: GD32F303RE, DAC: FIIO-developed R2R DAC, USB decoding: SA9312L, AMP: SGM8262-2*2
Color Black/Silver/Red Volume control Volume knob
Weight About 420g Dimensions 147x133x32.3mm (including feet)
Gain L/M/H Adaptive impedance PO: 8~150Ω
Driver-free mode (switch mode) Supported BAL: 8~350Ω
Oversampling setting OS/NOS FIIO Control N/A
Max supported sampling rate 384kHz-32bit/DSD256 (USB DAC) Sampling rate indication                                      
LOGO indicator light shows as default: Cyan: 48KHz and below/Yellow: above 48kHz/Green: DSD
Show on display screen  
192kHz-24bit (Coaxial)
96kHz-24bit (Optical) Firmware upgrade Supports upgrade through USB
Buttons and Ports
Knob Encoder knob (including volume adjusting and menu confirming) USB Type-C (data transmission)
Single-ended line-out RCA port Digital optical in Optical port
Digital coaxial in RCA port Digital coaxial out RCA port (only works in USB mode)
Balanced out Standard 4.4mm port Headphone out Standard 6.35mm port
Power Supply Parameters
Power supply DC 12V/2A Battery capacity No battery
Audio Parameters
Parts of performance and parameters of Line-out output (RCA, OS mode)
THD+N & Noise About 0.025% (1kHz/0dB@10KΩ) SNR ≥115dB (A-weighted)
Crosstalk ≥111dB Noise floor ＜5.1uV (A-weighted)
Frequency response 20Hz~50kHz: damping＜1.2dB Dynamic range ≥107dB
20Hz~20KHz: damping＜0.2dB Line output level 2.7Vrms
Parts of performance and parameters of headphone output (6.35mm, OS mode)
Output power L+R≥660mW +660mW(16Ω，THD+N＜1%) THD+N About 0.025% (1kHz/0dB@32Ω)
L+R≥460mW +460mW(32Ω，THD+N＜1%) SNR ≥115dB (A-weighted)
L+R≥50mW+50mW (300Ω，THD+N＜1%） Noise floor ＜7.2uV (A-weighted)
Channel crosstalk ≥72dB Dynamic range ≥107dB
Frequency response 20Hz~50kHz: damping＜1.3dB Output impedance ＜1Ω
20Hz~20KHz: damping＜0.2dB Peak output voltage 11Vp-p
Parts of performance and parameters of headphone output (4.4mm, OS mode)
Output power L+R≥520mW+520mW (16Ω, THD+N＜1%) THD+N About 0.025% (1kHz/-11.6dB@32Ω)
L+R≥1300mW+1300mW (32Ω, THD+N＜1%) SNR ≥115dB (A-weighted)
L+R≥220mW+220mW (300Ω, THD+N＜1%） Noise floor ＜14.1uV (A-weighted)
Channel crosstalk ≥107dB Dynamic range ≥107dB
Frequency response 20Hz~50kHz: damping＜1.3dB Output impedance ＜1.5Ω
20Hz~20KHz: damping＜0.2dB Peak output voltage 23Vp-p

 

 

 

 

 

Test conditions: USB in, -5dB sinusoidal signal, H gain, 20Hz-50kHz, 6.35mm headphone out (32Ω load)

 

Red: Left channel; Blue: Right channel

Test conditions: USB in, -6dB sinusoidal signal, H gain, 20Hz-50kHz, 4.4mm BAL headphone out (32Ω load)

 

Red: Left channel; Blue: Right channel

Test conditions: USB in, -5dB sinusoidal signal, H gain, 20Hz-20kHz, RCA line-out (10KΩ load)

 

Red: Left channel; Blue: Right channel

Test conditions: USB in, 0dB sinusoidal signal, H gain, 6.35mm headphone out (32Ω load)

 

Red: Left channel; Blue: Right channel

Test conditions: USB in, -5dB sinusoidal signal, H gain, 20Hz-50kHz, 6.35mm headphone out (32Ω load)

 

Red: Left channel; Blue: Right channel

Test conditions: USB in, -11.6dB sinusoidal signal, H gain, 4.4mm BAL headphone out (32Ω load)

 

Red: Left channel; Blue: Right channel

Test conditions: USB in, -5dB sinusoidal signal, H gain, 20Hz-50kHz, RCA line-out (10KΩ load)

 

Red: Left channel; Blue: Right channel

Test conditions: USB in, -6dB sinusoidal signal, H gain, 20Hz-20kHz, 4.4mm BAL headphone out (32Ω load)

 

Red: Left channel; Blue: Right channel