R2R DAC Card (for XD05PRO only)

The "R2R DAC Card" is an interchangeable module that delivers natural silkiness and a pleasing sound with the XD05PRO. Based on the concept of "Mellow Vinyl Sound," it offers smooth sound quality reminiscent of authentic analog records.

◆A New R2R Experience Combining Analog Warmth and Precision
Many DACs use the Delta-Sigma (ΔΣ) method, which shows excellent S/N ratio and low distortion in measurements. However, they also have weaknesses such as "flat sound" and "plenty of information but diminished musicality." R2R, which utilizes resistance ratios, excels in the subtle fluctuations of the time axis, natural decay, and the natural presence of overtones. xDuoo has pursued a warmth similar to analog record playback of yesteryear, developing a unique architecture with a substantial and precise R2R resistor ladder combined with an FPGA correction algorithm. This provides an unprecedented lively sound, rich in micro-dynamics unique to R2R, with accuracy comparable to ΔΣ DACs.

◆32-bit Support. A Generous R2R Network Configuration with 64 Elements per Channel
The R2R method generates analog signals simply through resistance ratios, meaning there's no coloration from calculations, making it easier to achieve a more natural and analog-like sound. However, its design is challenging; insufficient resistance precision or temperature stability can directly lead to sound blurring or distortion.
This unit features a 32-bit resistance ladder network configured independently for the left and right channels. It is equipped with eight 64-channel analog switches and a total of 128 high-precision resistors, ensuring 1/1000 precision and low-temperature drift. This accurately renders harmonic components without muddying them, providing faithful and stable signal reproduction.

◆Digital Precision × Smooth Tones
FPGA-controlled algorithms and 57-bit accumulator processing correct minor resistance errors and phase shifts. By combining the 57-bit accumulator calculation algorithm with a unique hardware architecture, full DSD512 hardware decoding is achieved. Furthermore, a unified clock management system is adopted across the entire system, maximizing the phase stability of the left and right channels and minimizing jitter. This dramatically improves the restorability of musical signals, overcoming the "lack of precision" often associated with traditional ladder-type systems, and achieving a fusion of vintage charm and modern resolution.

◆NOS Delivers a Highly Realistic Sound Experience
Many R2R products process DSD signals via oversampling or digital filters. However, these calculations can introduce side effects like jitter and pre-ringing, affecting the purity of the musical signal. This unit, however, performs decoding without oversampling or adding unnecessary calculations, maintaining the original sampling rate. This minimizes signal path processing, reproducing an extremely analog-like, natural, and smooth sound. The natural decay of piano notes and the nuanced bowing of string instruments spread across the stage, offering a vivid realism where the performer's intent is felt without artificial emphasis, ensuring comfortable long-term listening.

*To use this product, you will need the included XD05PRO main unit OS update module and a firmware download environment. For update procedures, please refer to xDuoo (https://xduoo.net/firmware-download/) [PASS: xduoo].
*We offer a proxy update service for customers who have purchased genuine domestic R2R DAC cards.

※If the product is not yet on sale or out of stock, please select "Pre Order" (delivery up to 1 month). Release date: October 7, 2025