Network Audio Server

The Gustard S26 is a dedicated music server built for local, networked, and high-resolution digital audio playback. It combines a self-developed X86 motherboard, AMD Ryzen 5 5600U processor, in-memory playback architecture, and a multi-group linear power supply with global clock synchronization. With support for Roon Core, UPnP/DLNA, AirPlay, HQPlayer NAA, and direct digital outputs including IIS, AES, coaxial, optical, and USB, it serves as the central hub for your system. 

CelWare audio OS

The S26 runs CelWare Audio OS, designed specifically for audio processing with ultra-low latency. It strips out unnecessary system overhead and prioritizes audio tasks, helping reduce timing inconsistencies that can blur detail. 

CelPlayer playback system

CelPlayer uses in-memory playback and memory-direct hardware write mechanisms to reduce data transfer latency. By keeping audio data closer to the processing path, it minimizes interruptions from storage access and system processes, which helps preserve timing integrity.

AMD Ryzen processing platform

Powered by an AMD Ryzen 5 5600U with 6 cores and 12 threads, the S26 balances performance with efficiency. Its 7nm architecture and low thermal design allow passive cooling to remain effective, keeping mechanical noise out of the system while maintaining responsive operation for music libraries and streaming services.

Linear power supply architecture

A 120VA linear power supply feeds multiple independent low-noise LDO stages, each dedicated to specific subsystems such as FPGA, PCIe, and network interfaces. Partitioning power delivery reduces cross-interference, helping maintain stable voltage and cleaner signal paths throughout the device.

Multi-group power partitioning

Independent 3.3V LDO rails allow each subsystem to operate without being affected by load changes elsewhere. This isolation reduces electrical noise coupling between components, which is especially important for digital audio where small fluctuations can affect timing accuracy.

Global clock synchronization

A single-source clock generator drives PCIe, USB, and digital audio interfaces, keeping all subsystems synchronized. This reduces jitter, resulting in cleaner, more stable audio output across connected devices.

GCLK-02 clock module

The integrated GCLK-02 clock module uses PLL technology with 1Hz-level locking precision. It supports external 10MHz clock input via BNC, allowing you to integrate a higher-grade clock source if desired. 

Passive cooling system

Instead of fans, the S26 uses liquid-cooled copper heat pipes and chassis-based passive cooling. Eliminating PWM fan noise and vibration reduces both electrical and mechanical interference, helping maintain a quieter operating environment for audio playback.

Flexible PCIe and cable connections

Flat cable connections replace traditional rigid PCIe mounting in key areas, reducing vibration transfer and improving connection stability. 

Storage and expansion

The S26 includes a built-in 1TB NVMe SSD using 3rd-generation TLC 3D NAND. It also supports PCIe 3.0 x4 M.2 expansion up to 4TB. Moving music files to internal storage reduces reliance on external data transfer, which can improve playback consistency.

Digital output flexibility

The S26 provides IIS, AES, coaxial, optical, and USB outputs. IIS supports PCM up to 768kHz and DSD512, while AES, coaxial, and optical support PCM up to 192kHz and DSD64 via DoP. USB output depends on the connected DAC, giving you flexibility across different systems.

IIS digital interface control

The IIS interface supports multiple wiring modes configurable through the app or web interface. This allows compatibility with different DAC implementations and supports high-resolution formats including PCM 768kHz and DSD512.

Network and streaming support

The S26 supports Roon Core, UPnP/DLNA, AirPlay, Spotify, and HQPlayer NAA. With gigabit Ethernet and integrated playback services, it works as both a server and bridge within a networked audio system.

Control and access

Control is available through the Gustard app and a browser interface at s26.local. This allows access from phones, tablets, and computers without requiring additional software installation on every device.

Product highlights

• Dedicated music server with CelWare Audio OS
  
• In-memory playback with CelPlayer
  
• Self-developed X86 motherboard with optimized BIOS
  
• AMD Ryzen 5 5600U processor
  
• 120VA multi-group linear power supply
  
• Global clock synchronization system
  
• GCLK-02 clock module with external 10MHz support
  
• Passive cooling with copper heat pipes
  
• Multiple digital outputs including IIS, AES, coaxial, optical, USB
  
• 1TB NVMe storage with M.2 expansion up to 4TB
  
• Support for Roon, DLNA, AirPlay, HQPlayer, Spotify
  
• App and browser-based control

Specs

• Model: S26
  
• System: CelWare Audio OS
  
• CPU: AMD Ryzen 5 5600U, 6-core/12-thread, 2.3GHz base, 4.2GHz boost
  
• RAM: 8GB DDR4
  
• Storage: 1TB NVMe SSD
  
• Expansion: 1 x M.2 PCIe 3.0 x4 2280 (max 4TB)
  
• Digital outputs: IIS, AES, coaxial, optical, USB
  
• IIS: PCM 44.1kHz–768kHz, 16–32bit, DSD64–DSD512
  
• AES/coax/optical: PCM 44.1kHz–192kHz, 16–24bit, DSD64 (DoP)
  
• USB: dependent on connected DAC
  
• Network: 100/1000Mbps Ethernet
  
• Clock input: 10MHz BNC, 500Ω, 0dBm–20dBm
  
• Power supply: 120VA linear
  
• Power consumption: 30–40W
  
• AC input: 115V/230V, 50/60Hz
  
• Dimensions: 13.0 in (330mm) W x 10.2 in (260mm) D x 2.6 in (65mm) H
  
• Weight: 12.1 lb (5.5kg)

What’s included

• Gustard S26 music server
  
• Power cord
  
• User documentation