FiiO K13 R2R Silver

The FiiO K13 R2R DAC and Headphone Amplifier is a high-performance desktop solution designed for audiophiles who demand accuracy, power, and versatility. At its core is a fully differential 24-bit R2R resistor array DAC, composed of 48 precision thin-film resistors per channel for a total of 192 resistors across four channels. Each resistor features 0.1% accuracy and low temperature drift, delivering rich, musical sound with minimal distortion.

The fully differential architecture reduces noise and minimizes FFT harmonics, producing a darker, more refined music background. With support for LDAC Bluetooth, multiple input options including USB, coaxial, and optical, and both NOS and OS decoding modes, the K13 R2R offers an immersive and flexible listening experience for both headphones and preamplifier setups.

Dual Mode and Extensive Output
The K13 R2R provides NOS (Non-Oversampling) and OS (Oversampling) modes, catering to diverse listening preferences. NOS mode preserves the original sampling rate of recordings, delivering an authentic, organic sound that faithfully reproduces the source material. OS mode upsamples audio to a high resolution of 384kHz, providing superior clarity and detail across all frequencies.

The unit functions as both a preamplifier and power amplifier with wide-ranging outputs including XLR and RCA line connections, balanced and single-ended headphone outputs, and 2400mW of balanced output into a 32Ω load. This allows it to drive high-fidelity IEMs and headphones effortlessly while revealing every subtle detail of recordings, making it an ideal centerpiece for a high-end desktop audio system.

Precision Equalization and Fully Balanced Circuitry
FiiO has equipped the K13 R2R with a ten-band high-precision parametric equalizer that allows users to adjust or simulate headphone frequency response curves. Utilizing the XMOS XU316 platform and FiiO’s proprietary tuning algorithm, adjustments can be made through the FiiO Control app or web interface, offering presets like Retro PEQ or custom curves.

The amplifier features a fully balanced audio circuit, including the DAC, low-pass filter, volume control, and headphone amplifier, ensuring minimal interference, low distortion, and high dynamic range. Additional protections include gain control, headphone safeguarding, and POP noise elimination, all designed to provide a stable, reliable, and robust listening experience for demanding users across a wide range of headphones.

Specially Designed Power Supply
The K13 R2R employs a dual DC/AC power supply system for superior stability and minimal interference. A 30W built-in switching power supply is protected by an alloy nickel-plated shield, while an external DC input allows connection to high-performance linear power sources for alternative sonic characteristics. Multi-rail regulation with 18 low-noise LDOs and 5 DC-DC converters ensures clean and robust energy distribution.

Premium ELNA RA3 silk-film and specialized tantalum electrolytic capacitors provide stable power delivery, resulting in a natural, warm sound signature. This meticulous approach to power design guarantees that the amplifier and DAC sections operate at peak performance, maintaining high-resolution fidelity even under heavy load or with challenging headphone impedances.

Design, Connectivity, and User Features
The K13 R2R combines elegance with functionality through a minimalist unibody aluminum chassis and skylight design that showcases the R2R resistor arrays. A high-contrast HD LCD display provides real-time information on sampling rate, gain, volume, and output mode. Bluetooth 5.4 with LDAC, AAC, and SBC support offers high-resolution wireless audio playback.

Gain selection and independent volume curves adapt the amplifier to any headphone or IEM. Protection mechanisms guard against overheating and overload, while customizable RGB lighting indicates sampling rates and enhances visual appeal. Additional convenience features include a timer shutdown function, remote control, and multiple accessories such as cables, adapters, and a quick start guide, making the K13 R2R a complete, premium desktop audio solution.

Tech Specs
- Color - Silver
- Main control chip (MCU) - ESP32-S3
- USB chip - XMOS XU316
- DAC - Fully differential true 24Bit R2R DAC resistor arrays
- Volume control chip - NJW1195AV
- R2R and LPF op-amp - OPA1642*4
- LO buffer op-amp - LTA8092*2
- Headphone amplifier - OPA1642*2 + TPA6120A*2
- USB input - 384kHz/32bit, DSD256
- Coaxial input - 192kHz/24bit, DSD64
- Optical input - 96kHz/24bit
- USB connector - Dual Type-C
- Display - Custom LCD
- Power input - AC 100-240V 50/60Hz; DC 12V/2.5A
- Dimensions - About 210 x 188 x 42 mm (including feet)
- Weight - About 980g
- Single-ended power output 1 - L+R≥1220mW +1220mW (32Ω, THD+N1%) (32Ω/SE/high gain)
- Single-ended power output 2 - L+R≥150mW+150mW (300Ω, THD+N1%) (300Ω/SE/high gain)
- Balanced power output 1 - L+R≥2400mW+2400mW (32Ω, THD+N1%) (32Ω/balanced/high gain)
- Balanced power output 2 - L+R≥600mW+600mW (300Ω, THD+N1%) (300Ω/balanced/high gain)
- Frequency response - 20Hz~80kHz: Attenuation2.9dB
- SNR - ≥116dB (A-weighted)
- Noise floor - PO9uV (A-weighted); BAL18uV (A-weighted)
- Output impedance - PO0.7Ω (32Ω load); BAL1Ω (32Ω load)
- THD+N - About 0.0173% (1kHz/-6dB@32Ω)