T1 10MHz Time Reference

When it comes to digital systems, time counts – literally. The precise placement of data, the individual samples that constitute the musical signal, is critical to the accurate reproduction of the original signal. Any drift or error in the spacing of the samples will quickly erode the integrity of the signal, which is why designers of digital systems go to such great lengths to ensure the accuracy of the master clocks that provide a time domain reference for reading data, its transfer and decoding. This reduction in jitter has become the holy grail of digital design.

“The T1 Time Reference let loose a barrage of detail beyond anything I’ve heard from digital source… But it was not a lopsided advance on the analytical front alone. It was balanced with enhanced timbre, full tone, and especially pace, rhythm and timing.”


Product Description

The problem is, that as soon as you have more than one box (and one master clock) in the system – for instance, if you use a transport and DAC – then the errors can increase exponentially. The easiest solution is to synchronize the two clocks, designating one as the master and slaving the other to it. That’s exactly the solution provided by the Clock-Sync cards available for the CH Precision D1, C1 and I1, while the sophisticated software control incorporated into each of the units allows owners to designate master and slave according to circumstances and system topology. But what’s better than syncing two or more units to a single master clock? Syncing them all to a single, superior, external reference point – a reference like the T1 Time Reference external clock.

The T1 generates a super accurate, low-jitter signal that delivers measurably lower phase noise and more accurate transfer and conversion of digital signals. It is built around a high-frequency 10MHz oven controlled oscillator (OCXO), its core temperature and output further stabilized by encapsulation in a mechanically isolated billet aluminum block. Why not just use one of the popular and readily available Rubidium clock modules like everybody else? Because those Rubidium modules have a limited life span – generally between six and eight years – and they contain radioactive material. At CH Precision we expect our products to have a much longer working life than that, so incorporating components with a finite life is contrary to all our beliefs – especially if those components then present a serious disposal issue.

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  • High-Frequency (10MHz) delivers superior accuracy
  • Square wave: 1V or 500mV peak to peak, selectable
  • Sine wave: 1V or 500mV peak to peak, selectable
  • 6 outputs, 75Ω BNC coaxial
  • Transformer-coupled outputs to further limit phase noise and error
  • Independent control for each output


  • GPS input for CH Precision GPS time constant option
  • 1 pulse per second (1 PPS) TTL signal for external synchronization
  • Ethernet for remote control (CH-Control App)
  • USB for firmware upgrade

Power Supply

  • Dedicated ultra low noise, three-stage, discrete regulated linear power supplies for each section
  • Galvanically isolated power supplies for the OCXO, the OCXO buffer and the output buffers/li>
  • Magnetically and electrostatically shielded toroidal mains transformer/li>

Physical Arrangements

  • OCXO mounted inside a heavy aluminum block for even greater stability of critical core temperature
  • Complete OCXO housing mounted on soft silicon gel for maximum damping and isolation from vibration
  • Power transformer mechanically isolated to reduce internal vibration

Optional Hardware

  • Unlike other CH Precision units, the T1 offers only one option – its unique GPS input
  • Instead, the T1 is itself the option, offering improved performance with all CH Precision digital components (the D1, C1 and I1) a vital part of their scalable, upgradable topology

Technical Specifications

Nominal frequency
10MHz, +/- 20ppb, internal mode
10MHz, +/- 1ppb maximum, GPS option locked for 1 hour

Phase noise performances
< -105dBc/Hz @ 1Hz
< -125dBc/Hz @ 10Hz
< -145dBc/Hz @ 100Hz
< -155dBc/Hz @ 1kHz
< -165dBc/Hz @ 10kHz and above

Outputs level
500mV or 1V, peak to peak, loaded with 75Ω
Sine or Square wave
Six 75Ω BNC outputs

External Reference Input level
50Ω BNC input

Accepted Reference input frequencies
1 PPS, 44.1kHz, 48kHz, 88.2kHz, 96kHz, 176.4kHz,
192kHz, 100kHz

Reference input frequency deviation maximum
+/- 0.1ppm

440 x 440 x 133mm (W x D x H), 20kg

T1 Specific Downloads

CH-Control App

Meet the CH-Control App – a control application that allows users direct access to every aspect of their CH system’s set up and use via any Android portable device. The software control systems used to set and monitor the operational parameters of each and every CH component offer the perfect opportunity for remote operation via a portable App.

To use the CH-Control App, all you will need is an Android device and to connect your CH components to an Ethernet network. That can be done either through the Ethernet control board fitted as standard to all CH units, or through the network streaming board that can be installed in C1.2, C1.2 Mono or I1 units. We would always recommend using a dedicated tablet and network for your music streaming and system control requirements.

Once your CH system is all hooked up, the App gives you touch screen access to every setting on every CH component, from your listening seat, a huge benefit when it comes to whole system set up or optimization for individual recordings. Either way, the CH-Control App allows you to make easier and more accurate judgements: Total control, quite literally at your fingertips.

The features of every CH product are accessible through the CH-Control App:

  • Built-in UPnP controller to stream dematerialized music, create playlists, etc.
  • Set volume level, select sources, reverse phase, mute, etc.
  • Access to all the advanced set-up parameters in every CH product.
  • Works on a standard Ethernet network.
  • The CH-Control App is freely available on Google Play.