FiiO K13 R2R DAC & Balanced Headphone Amp w/ 4.4mm output. OPEN BOX unit, complete, full warranty, very good condition. The K13 R2R uses FIIO’s proprietary four-channel fully differential 24-bit R2R resistor array DAC - designed in house to FiiO's specs, the K13 uses a total of 192 tightly matched resistors across four channels for native balanced output. The K13's R2R DAC allows the it to deliver a uniquely rich and musical sound that is so in demand today. There are two processing modes built in that you can choose from, the NOS (Non-Oversampling) and OS (Oversampling) modes. These modes create two slightly different listening experiences, with one smoother and the other with more emphasis on the clarity, detail and sharper in the highs, to let you better match its tuning to your favorite headphone. The board for the DAC is as shown below: Robust Headphone AMP Strutting a big ole balanced output power of 2400mW into a 32 ohm load, FiiO K13 R2R can effortlessly drive both high fidelity IEM's and full size headphones, unlocking their full potential and allowing them to render every last detail. K13 R2R is designed with DC/AC dual power supplies. The built-in 30W switching power supply is shielded by a nickel alloy shielding cover to isolate it from the other components in the amp and try to have the cleanest power supply possible. Additionally, it also features an external DC power input, allowing you to pair it with a higher-performance linear power supply for a different sound experience. (FiiO will launch a matching linear power supply to market in 2026, using the same housing and finish, that would stack under the K13. ) That said, the built in power supply did not cut a corner - K13 R2R employs a multi-rail power supply to provide strong and clean power for uninhibited analog headphone audio output. Premium ELNA capacitors and other audiophile quality caps come together and contribute to the high quality internal power supply that drives the K13 and supports the warm and natural K13 tuning. Preamp, Desktop Audio Hub With a wide variety of inputs and outputs, the K13 R2R functions as both a preamplifier and a headphone amplifier, ideal to have at your desk for almost any combination of sources and gear. K13 R2R also supports PCM 384kHz/32bit and DSD256 decoding - making the K13 R2R perfect for Apple Music Lossless or Tidal, to decode all the high res audio files and provide tons of headphone power, headroom and dynamics, with a huge variety of headphones. FiiO K13 included accessories: Remote, usb-c cable, 6.35mm adaptor FiiO K13 R2R Technical Specifications: Category Specification Details Audio Architecture DAC Topology 24-Bit Fully Balanced R2R Resistor Array Decoding Modes OS (Oversampling) & NOS (Non-Oversampling) Hi-Res Support Up to 384kHz/32-Bit, DSD256 Parametric EQ 10-Band PEQ (App/Web via USB) Amplification Power Balanced Output 2400mW @ 32Ω (4.4mm Jack) Single-Ended Output 1220mW @ 32Ω (6.35mm Jack) Output Impedance Balanced: <1Ω / Single-Ended: <0.7Ω Performance SNR: 116dB / THD+N: 0.0173% Gain Control 3 Adjustable Gain Levels Connectivity Digital Inputs USB-C (Back & Side), Coaxial, Optical Analog Line Out Balanced XLR Out / Dual RCA Out Bluetooth 5.4 Input support for LDAC, SBC User Interface Display High-Brightness Always-On LCD Visual Effects Adjustable RGB Lighting (Color & Brightness) Utility Features Timer Shutdown (1–99 mins) Physical & Build Dimensions 21.0 x 19.0 x 4.2 cm Weight 980g Chassis Aluminum Unibody with "Skylight" Window Why Buy From FiiO Canada? When you purchase from fiiocanada.ca, you aren't just getting a product; you’re getting peace of mind. Fast Canadian Shipping: No surprise customs fees or long waits from overseas, ships from our Toronto head office. Local 1 Year Warranty Support: We handle all warranty claims right here in Canada.