Master Fidelity's NADAC S Server Begins Shipping, Running the Whole Computer From One 10MHz Reference

GTT, Master Fidelity's North American distributor, announced on 8 September 2026 that the NADAC S music server has begun shipping. The announcement — datelined Long Valley, New Jersey, and reproduced by The Absolute Sound the following day — arrived alongside a filmed conversation with Master Fidelity's Weishen Xu, and it closes out a system rather than opening one. The NADAC S is the third box in a front end that already comprised the NADAC D converter and the NADAC C master clock.

The argument: one reference, many clocks

The premise Master Fidelity puts behind the NADAC S is worth stating carefully, because it is more specific than the usual clocking pitch. In a conventional computer-based front end, the source machine and the converter can be running from entirely independent timing references. Fitting a precision clock at the converter, the company argues, does not by itself do anything to coordinate the many clocks scattered through the computer feeding it.

In the GTT film, Xu puts this in plain terms: a server contains a whole population of clocks — the chipset, the network interfaces, the storage path — each running at its own frequency, and left to themselves they never talk to one another. Given a single reference, they do. That framing comes from the manufacturer, and it is the thesis the NADAC S is built to demonstrate.

Master Fidelity is also explicit that the distinguishing feature is not the mere presence of a reference-clock input. Other high-end servers offer one. What the company says sets the NADAC S apart is how far the reference travels once it is inside the box: a custom motherboard distributes reference-derived timing across the computing platform and onward into purpose-built USB and network interfaces, with power supplies tailored to the role each section plays.

How the clocking actually works

The NADAC S accepts a 10MHz reference over BNC — for synchronisation to the NADAC C — or runs from an internal oven-controlled crystal oscillator when no external reference is present.

The link from server to converter is described by Master Fidelity as a synchronous USB connection carrying small, synchronised packets. One point here is easy to garble and worth getting right: the external 10MHz reference is not the converter's working clock. The NADAC D continues to use its own Advanced Clock Data Recovery to generate the final conversion clocks demanded by its true 1-bit architecture. The shared reference coordinates the system; it does not replace the converter's own clock generation.

Master Fidelity does publish a jitter specification for the NADAC C's 10MHz output — 66 femtoseconds, measured across 10Hz to 100kHz — but that figure belongs to the clock, not to the server, and should not be read as a NADAC S specification.

Connections, storage and cooling

The connection set is short and pointed rather than generous. Per the manufacturer's own listing:

• A locking USB-C port dedicated to the NADAC D.
• Two selected USB-A ports.
• Custom RJ-45 and SFP network interfaces, all on low-noise linear power. The SFP interface ships with an optical-fibre adapter.

Storage is split between an enterprise U.2 system drive and four enterprise SATA SSDs for the music library. The machine runs fanless, with no moving parts anywhere in the chassis — a design choice that follows naturally enough from an all-solid-state storage arrangement. Master Fidelity has not published capacities, processor details, memory, dimensions or weight in the material behind this announcement, so none of that is settled here.

Software

Windows 11 Enterprise LTSC is installed by default, with Linux alternatives supported. LTSC is the long-term-servicing branch of Windows, which is a sensible fit for an appliance that a customer will expect to behave identically in three years' time. Master Fidelity says it validates and stress-tests Roon, HQPlayer, Audirvana and JPLAY, among others, on the platform.

Availability and price

The NADAC S is shipping now, in limited quantity, on an order queue. That is the entirety of what has been established about availability — no lead time, no delivery date, no production figure.

No price has been published. The Absolute Sound withholds pricing in its coverage and directs readers to GTT or an authorised dealer for pricing, configuration, delivery timing or a demonstration; Part-Time Audiophile's report likewise arrived without a figure. Any number circulating on third-party aggregator listings is unconfirmed by the manufacturer, its distributor or either of the trade outlets covering the launch, and we are not going to repeat one. GTT is the named North American distributor; nothing has been established about distribution elsewhere.

What is claimed, and by whom

Every performance statement attached to the NADAC S at this stage originates with Master Fidelity or GTT. That is normal for a shipping announcement, but it is worth naming plainly, because clocking is a subject where enthusiasm tends to outrun evidence. Recording engineer Bert van der Wolf-Oude Avenhuis has written about Master Fidelity's clocking technology in recording and playback contexts — but that essay dates from February 2024, predates the NADAC S entirely, and cannot be read as an assessment of this server.

What can be said without qualification is that the NADAC S is an unusually literal expression of a single idea. Rather than treating the computer as an unavoidable source of noise to be isolated after the fact, Master Fidelity has built a machine whose internal architecture is organised around one incoming reference signal, and then handed the final conversion clocking back to the converter where it belongs. Whether that architecture earns its keep is a question for listening, and the notes available at launch do not answer it. Prospective buyers are pointed to GTT or an authorised dealer for a demonstration.

Further manufacturer detail is on the Master Fidelity NADAC S product page, and the conversation with Weishen Xu is GTT Episode 160.

Frequently asked questions

What is the Master Fidelity NADAC S music server?

The Master Fidelity NADAC S is a fanless music server that began shipping in North America on 8 September 2026 through distributor GTT. It forms a three-box front end with the NADAC D converter and NADAC C master clock, sharing a single 10MHz timing reference distributed across a custom motherboard and into purpose-built USB and network interfaces.

How does the Master Fidelity NADAC S use a 10MHz clock reference?

The NADAC S accepts a 10MHz reference over BNC for synchronisation to the NADAC C master clock, or runs from an internal oven-controlled crystal oscillator. Master Fidelity says a custom motherboard distributes reference-derived timing across the computing platform and into its USB and network interfaces, each on power supplies tailored to their roles.

Does the 10MHz reference become the NADAC D's conversion clock?

No. Master Fidelity states that the external 10MHz reference is not the converter's working clock. The NADAC D's own Advanced Clock Data Recovery still generates the final conversion clocks required by its true 1-bit architecture. The NADAC S to NADAC D link is a synchronous USB connection carrying small, synchronised packets.

What operating system and storage does the Master Fidelity NADAC S use?

The NADAC S ships with Windows 11 Enterprise LTSC installed by default, with Linux alternatives supported. Storage comprises an enterprise U.2 system drive plus four enterprise SATA SSDs for the music library. The server operates fanless with no moving parts. Master Fidelity says it validates and stress-tests Roon, HQPlayer, Audirvana and JPLAY, among others.

How much does the Master Fidelity NADAC S cost?

No price for the Master Fidelity NADAC S has been published. The Absolute Sound withheld pricing in its 9 September 2026 coverage and directed readers to GTT, Master Fidelity's North American distributor, or an authorised dealer for pricing, configuration, delivery timing or a demonstration. The server ships in limited quantity on an order queue.

This article was written by an AI system from Into The HiFi AI Desk, generated from the following sources, with no human editing pass before publication: The Absolute Sound — Master Fidelity's NADAC S Music Server (9 September 2026), Part-Time Audiophile — NADAC S Music Server from Master Fidelity Debuts (9 September 2026), Master Fidelity — NADAC S product page (manufacturer), GTT Episode 160 — conversation with Master Fidelity's Weishen Xu.