XACT Audio S1 Music Server

A new benchmark for digital audiophile experience
XACT S1 takes digital audio playback to new heights with its naturally sophisticated sound and high-class user experience.

Created by Marcin Ostapowicz, the founder of JCAT and JPLAY brands and author of some of the most innovative high-end audio products, including the world’s first audiophile network card.

Personal audio quest fulfilled.
The creation of XACT S1 stems from my quest to create superbly sounding digital audio transport for myself, which brought me into high-end audio hardware development.

A lifetime of experiences inside.
S1 synthesizes all my audio research findings and experience in developing innovative audiophile hardware (JCAT) and software (JPLAY). Every product I’ve developed over the years has made an important contribution towards the creation of XACT server.

6 years of development and tuning.
XACT S1 is a unique device created entirely from the bottom up. The development of the server in this shape started in 2016. After 3 years, I’ve had a final motherboard. The following 3 years were strictly dedicated to fine-tuning. This is a device I’ve worked on the most in my entire life.

Designed and developed from square one. Fine-tuned by ear. Obsessively.

Not an another PC.
A completely new device.
Most streaming products available today are made with standard, ready-to-use mini-PC motherboards designed for office or home entertainment. However, these motherboards have noisy power converters that interfere with other hi-fi components and produce an irritating “digital” sound. Some companies try to mitigate the issue by upgrading their power supplies, but this doesn’t address the root cause. That’s why developing an entirely new motherboard from scratch with only audio playback in mind was the only way to go with XACT S1.

100% linear power delivery.
Truly everywhere.
It’s the first music server that puts so much emphasis on power quality ever. The motherboard itself has only linear regulators and runs solely on linear power. The dedicated power source is 100% linear without any switching components. XACT S1 delivers unmatched electrical performance. There’s nothing else like it.

Extensively ear-tested with every tweak
Hardware and software in harmony. The definition of synergy.
Over more than 10 years of developing JPLAY, I’ve learned firsthandedly that the software has as much impact on the sound quality as the hardware platform itself. Through meticulous testing, I’ve explored all possible optimizations of the operating system and player’s code, ultimately identifying the most harmonious combination for the S1’s hardware.

Fine-tuned by ear with every minor change. For years.
I’ve done extensive listening on S1 every time I tweaked something. Every minor change was tested and logged by me personally. Every hardware component, every OS update, every modification of settings.