↓ Details provided by FiiO ↓
(Specifications and appearance of this product are subject to change without notice)

Fully differential True 24bit R2R DAC Resistor Arrays

FIIO's newly self-developed four-channel fully differential 24bit R2R DAC consists of 2x 48 precision thin-film resistor arrays per channel, totaling 192 resistors with 0.1% tolerance and low temperature drift (30ppm). This configuration delivers a unique and charming sound.

Double the fun Dual NOS/OS modes

NOS (Non-Oversampling) Mode: Maintains the original sampling rate for decoding, preserving authentic sound and allowing you to enjoy an organic and captivating musical experience. OS (Oversampling) Mode: Upsamples globally to a high sampling rate of 384kHz, for superior audio performance and even more refined, clear sound.

True 24bit decoding Excellent capabilities, outstanding sound quality

Support for PCM 384kHz/24bit and DSD256 decoding, means the K11 R2R can easily handle high-precision audio signals and fully exhibit the details within, providing you with an excellent audio experience. * DSD256 requires setting the DSD output mode to Native on the source device, internally converting to PCM before being decoded by the R2R resistor arrays.

NJW1195A High quality electronic volume control

The NJW1195A is a 4-channel electronic volume controller. This resistor ladder electronic potentiometer is low distortion and low noise, allowing precise volume adjustment.

3 gain levels+ 3 independent volume curves

The 3 independent gain levels and volume curves allow the K11 R2R to give you a better listening experience with various types of headphones, whether you are using sensitive earphones or harder to drive over-ear headphones.

Digital audio bridge: Specially-designed audio circuit

The audio signal is transmitted via a USB interface processor to a digital audio bridge. After being processed by an FPGA, it is sent to the R2R DAC for 4-channel output after decoding. Then, it passes through two Ti OPA1642 op-amps for low-pass filtering and single-ended analog signal converting, and transmits to the NJW1195A electronic volume control chip for precise volume adjustment. The output stage uses two SGM8262 op-amps for 4-way phase inversion and amplification, resulting in outputs of singed-ended and balanced analog signals.
The audio circuit features gain controls. It is complemented by a specially-designed headphone protection circuit and a pop noise elimination system, ensuring the audio circuit is both high quality in sound produced and reliable.

Specially-designed power supply

The K11 R2R uses up to 17 low-noise LDO precision regulator IC and 2 DC-DC converters, providing multi-channel specialized power supply of -9V, 8V, ±7.5V, ±6V, 5.4V, 3.3V, 1.8V, and 1.2V. These are combined with an external custom 12V switching power supply to ensure the purity of the power supplied and provide a solid foundation for stronger power output.

The capacitors' ultra-low ESR, combined with excellent anti-interference capabilities, allow them to provide a stable and clean power supply and thus achieve high-quality sound.

High-quality Beryl solid capacitors

The capacitors' ultra-low ESR, combined with excellent anti-interference capabilities, allow them to provide a stable and clean power supply and thus achieve high-quality sound.

Powerful output: Hear every last detail

Under a 320 load, the K11 R2R is capable of pushing 1300mW+1300mW under balanced modes. This allows it to easily drive many HiFi earphones and headphones to fully unlock their potential.

Full of clarity: A beautiful screen

A custom, high-contrast and durable LCD screen* allows you to easily see the sampling rate, volume, gain, or output mode with just a glance.
*Durable LCD screen, always on with no burn-in

One source of total control

The K11 R2R's multi-function volume knob is used to power the device on and off, for menu operation, for volume adjustment, and for other functions. The knob is designed so that you can quickly execute various complex actions by simply pressing and turning the knob. You can also quickly switch between PO/PRE (LO SE)/LO* modes by double-pressing the knob, making it easier for you to appropriately connect to different audio setups.

Adjustable RGB logo lighting

The FIIO logo is illuminated with RGB lighting, giving you a quick way to identify the sampling rate of the current audio being played back. Six LED strips work in conjunction with carefully placed reflective film and parts of the body designed to reflect light to make the light show uniform and elegant.

Safe and reliable Comprehensive safety systems

RCA metal pressing for enhanced stability, reliable connection, and durability

Headphone amplifier heat dissipation upgrade

A stable combination of thermal silicone gel and aluminum alloy ensures fast heat dissipation

Exclusive phosphor copper metal shielding

The shielding cover undergoes a passivation process, providing corrosion resistance and anti-oxidation capabilities. It effectively resists external interference, ensuring signals processed are accurate.

IN THE BOX

1. K11 R2R
2. Power adapter
3. Power cable
4. USB data cable
5. Headphone adapter
6. Quick start guide
7. Warranty card

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	Show on display screen
	192kHz-24bit (Coaxial)	LOGO indicator light shows as default: Cyan: 48KHz and below/Yellow: above 48kHz/Green: DSD
Firmware upgrade	96kHz-24bit (Optical)	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