C1.2 Digital to Analog Controller

C1.2 Digital to Analog Controller

Sometimes, what you want is exactly what you get. Take the C1.2 DAC/Controller as an example: You want a world-class DAC with leading edge digital design and cutting edge musical performance? You’ve got it. You want a control unit to switch multiple digital inputs and control level? You’ve got it. You want to accept and switch analog inputs? You can do that too. You want a product that‘s future proof in terms of price AND performance? The C1.2 ticks that box as well! In fact, the C1.2 is any or all of those things; you get to choose…

Normally, creating a world-class DAC could be considered a sufficient challenge on its own, but the use of modular component architecture and the power of sophisticated software control opens up opportunities as well as offering solutions: opportunities that transform the role, capabilities and versatility of the C1.2 – as well as allowing existing C1 units to be upgraded to full C1.2 standard.

“It’s this ability to deliver both top-notch performance and unprecedented levels of versatility and user choice that absolutely sets CH Precision apart from its competitors.”


C1.2 Digital to Analog Controller

Of course, it is digital conversion that lies at the heart of the C1.2. The perfect preservation of time and amplitude information is critical to reproducing musical signals stored in digital formats and we believe that the advances incorporated in the C1.2 build significantly on the solutions adopted in the C1, taking digital performance(s) to a whole new level.

Both noise and jitter are central to the design of any high-performance DAC. We have developed an entirely new MEMS-based, shunt regulated and thermally compensated clock for the C1.2, improving clock accuracy significantly (as well as providing highly developed clock-sync and external reference clock options). A four-fold increase in processing power has allowed us to further refine the proprietary CH-PEtER algorithms, introduce 32-bit fixed point processing and increase input compatibility to include all high-resolution digital formats, whether from optical or file replay sources. Our proprietary CH-Link HD interconnection allows the transfer of native DSD and MQA data in the digital domain, from the D1.5 transport to the C1.2. The AES/EBU and S/PDIF inputs accept PCM at up to 192kHz/24bit resolution, while the HD streaming input will accept PCM data at up to 768kHz/32 bit resolution and DSD512(8x). Local regulation of the DSP and FGPA further reduce the system noise floor. The DAC itself employs no fewer than four converter chips per channel, in a fully differential, dual-mono topology. The vital analog output stage is discrete, fully differential, Class-A and DC coupled. The modular input architecture ensures that the C1.2 remains future proof, able to adapt to changing digital standards or system demands.

Having created the C1.2’s digital decoding core, the next step was to construct the system architecture around it. As well as the established digital input standards (AES/EBU, S/PDIF and TosLink) the provision of separate Ethernet streaming and USB input cards allows users to configure the C1.2 specifically to their system and replay requirements. Alongside the multiple digital input and clock-sync options, there is also a by-passable hybrid volume control, operating across both the analog and digital domains and an A-to-D facility, allowing the C1.2 to accept balanced or single-ended analog inputs, creating a genuine analog/digital domain control option, allowing the C1.2 to stand at the center of any system, irrespective of the source components in use.

With the vast array of user definable parameters on offer, from input offsets for both analog and digital connections, to balance, output level and absolute phase, a comprehensive, non-intrusive display is essential. This requirement led directly to the creation of our latest 800 x 480 pixel AMOLED screen, with its user-configurable content, brightness and power-down options. Users can even select a specific RGB color for the content! Although each and every setting in the C1.2 can be accessed and adjusted from the dual-concentric control on the front-panel, the CH App allows direct, remote access to every parameter from an Android tablet or smartphone, making this not only one of the most adjustable, configurable and adaptable DAC Controllers on the market – but also one of the easiest to use.

Standard Inputs

  • Factory fitted with CH-Link HD, AES/EBU, S/PDIF and Toslink digital inputs.
  • The CH-Link HD interface allows for synchronized transfer of high definition audio content (up to 32bit/768kHz) and DSD512 (8x), offering the ideal interconnection to the D1.5 CD/SACD Transport or other CH-Link HD equipped units.
  • Standard digital inputs accept PCM to 24bit/192kHz, DSD 1bit/2.822MHz (DSD over PCM or DoP-encoded).

Optional Digital Inputs

  • The C1.2 can accept up to three digital input boards to allow multiple digital sources to be connected.
  • Ethernet audio streaming HD input board (UPnP/DLNA compatible) allows connection to local audio servers (such as NAS drives running a UPnP server) or streaming services (such as Qubuz, Tidal or webradios).
    PCM to 24bit/384kHz (768kHz for uncompressed formats)
    DSD 1bit/2.8224MHz (DSD64), 5.6448MHz (DSD128), 11.2896 MHz (DSD256) or 22.5792MHz (DSD512)
    Native DSD and DoP
    WAV, AIFF, FLAC, ALAC, AAC and MP3 formats supported in PCM
    DSF and DFF formats supported in DSD
  • Asynchronous USB audio streaming input board – PCM to 24bit/384kHz, DSD 1bit/5.6448MHz (DSD128) in DoP Mode

Digital to Analog Conversion

  • Four PCM-1704 R-2R converters per channel
  • Fully complementary, dual mono symmetrical circuit topology
  • Discrete, dedicated, fully regulated linear power supplies for low noise and maximum channel separation


  • Four independent 2.4GFLOPS DSP engines for each channel
  • Proprietary CH-PEtER 32-bit fixed point, synchronous data over-sampling processing
  • Direct DSD to 705.6kHz, PCM conversion
  • Resolution enhancement of audio material recorded at less than 24bits
  • Full MQA decoder (unfolding and rendering) at 24bit/768kHz.

Timing & Clocking

  • Ultra low jitter MEMS-based, thermally compensated Master Clock with dedicated, shunt regulated power supply
  • Optional Master/Slave Clock-Sync board allows synchronization with T1 10MHz Time Reference clock or other 10MHz external clocks.
  • Clock-Sync board also synchronization with the D1.5 CD/SACD transport.

Volume Control

  • By-passable 0.5dB step hybrid volume control, course steps using a relay/resistor ladder, with fine steps in the digital domain, to maximise system resolution.
  • Channel balance in 0.5dB steps
  • Switchable for mono (input L + input R) output.
  • Switchable absolute phase

Analog Input Board

  • Discrete, fully differential analog input circuit
  • Balanced XLR and single-ended RCA inputs
  • 6V RMS maximum input level
  • Input gain is user selectable
  • Up to two Analog input boards can be fitted, providing a maximum of two balanced XLR and two single-ended RCA inputs.

Analog-to-Digital conversion

  • • DSD 1bit/5.6448MHz (DSD128) direct conversion

Analog Output Stage

  • Pure class A, fully symmetrical circuit
  • Fully discrete, ultra low noise, high slew rate design
  • Zero global feedback
  • One pair each – balanced XLR, single-ended RCA and BNC outputs
  • DC coupled
  • 5.4V maximum output (balanced XLR), 2.7V maximum output (single-ended RCA/BNC)


  • 800 x 480 pixel, 24bit RGB AMOLED
  • 7 standard, user-selectable text colors
  • User definable RGB option for text color

Remote Control Options

  • Infrared Remote Control handset for basic functions
  • Ethernet-based Android control App

Optional Hardware

  • Digital Input Board – CH-Link HD, AES/EBU, S/PDIF and Toslink
  • Ethernet Network Streaming HD Input Board
  • Asynchronous USB Input Board
  • Clock-Sync Board
  • Analog Input Board – One pair balanced XLR, one pair single-ended RCA
  • Fully compatible with X1 External Power Supply
  • Compatible with T1 10MHz Time Reference external clock (with Clock-Sync board)

Conversion type

  • Linearized R-2R, 4x PCM1704 per channel
  • 24 bit / 705.6kHz & 768kHz

DSP processing

  • CH-PEtER upsampler, synchronous, DSD to PCM conversion and resolution enhancer

Full scale analog outputs level

  • 5.1V RMS balanced
  • 2.55V RMS single-ended

Signal to Noise Ratio

  • > 120dB

Total Harmonic Distortion + Noise

  • < 0.004%, full scale, 22kHz BW


  • 20kg per unit


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

C1.2 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.