Gustard and Amanero’s precision-built digital bridge

The Gustard U26 is a professional-grade USB digital interface designed to bridge computers and digital-to-analog converters (DACs) with near-zero jitter and exceptional electrical isolation. Co-developed with Amanero Technologies in Italy, it employs an ARM Cortex-M7 processor, temperature-controlled OCXO and K2 PLL clocks, and independent linear power regulation to deliver stable, ultra-clean digital output. With support for native DSD up to DSD2048 and PCM up to 1.536MHz, the U26 serves as a precision link for high-end DACs and digital playback systems.

A bridge built for precision

At its core, the U26 is a digital bridge. It receives USB audio signals, reclocks and reshapes them, and outputs via IIS, AES, or coaxial with remarkable timing accuracy. The Amanero USB interface is deeply customized for low-latency data transfer, ensuring that digital audio reaches your DAC without distortion or jitter introduced by timing errors. This precision is measurable—signal transmission remains stable even at extreme sampling rates.

Isolation from the source

PCs and servers are inherently noisy, generating ground loops and high-frequency interference that can leak into the audio signal. The U26 solves this with a 200Mbps full-isolation chip that physically separates the USB input from the rest of the circuit. It eliminates noise coupling and protects delicate clock and signal paths, maintaining a clean, interference-free digital stream.

Temperature-controlled clocking

The heart of the U26’s accuracy lies in its OCXO (oven-controlled crystal oscillator) and K2 PLL clock system. These temperature-stabilized oscillators maintain ±0.1ppm precision, generating dual low-phase-noise clock signals at 98.3040MHz and 90.3168MHz. In practice, this means better synchronization between your source and DAC, lower jitter, and a perceptible reduction in digital harshness.

CPLD signal shaping

Even after isolation, some timing errors can remain. To counter this, the U26 uses a complex programmable logic device (CPLD) to reshape IIS signals and remove additive jitter. By rebuilding the waveform at the hardware level, the device delivers perfectly timed digital signals to the DAC, improving transient accuracy and preserving microdetail.

Independent power architecture

Digital precision depends on stable power. The U26’s dual linear power supply—built around a high-grade toroidal transformer—provides separate regulated rails for the USB and digital circuits. This isolation prevents interference between modules and minimizes high-frequency noise. A total of 80,000µF of filtering capacitance ensures current stability during dynamic peaks, while dual rectifier bridges and discrete transistor regulation maintain consistent performance over time.

Custom Amanero driver control

Windows users can access Gustard’s custom ASIO driver interface for flexible tuning. Adjustable buffer and latency parameters allow the user to optimize for stability or response time. Fine adjustments to clock phase and data alignment offer control over timing and resolution—features aimed squarely at those who prefer to manage every variable in their signal path.

Full-format digital compatibility

The U26 supports PCM streams up to 32-bit/1.536MHz and DSD up to DSD2048 in both DoP and native modes. Optical, AES, coaxial, and dual IIS-LVDS outputs (one configurable) provide broad compatibility with DACs and amplifiers. For studio and reference applications, an external 10MHz clock input enables precise synchronization with master clock systems.

Built to last

Machined from aluminum alloy, the U26’s chassis offers both electromagnetic shielding and structural rigidity. Internally, the layout separates analog and digital domains with careful trace routing and physical distance between the transformer and signal paths. The result is a quiet, mechanically stable component that integrates neatly into any desktop or rack system.

Who it’s for

The U26 is built for listeners who want complete control over their digital audio chain. It’s a fitting choice for DAC owners looking to add galvanic isolation and high-accuracy clocking to their systems, or for studio users who need stable digital signal distribution without added noise or phase drift. 

Availability

The Gustard U26 USB Digital Interface is available now on Apos Audio.