C1 Digital to Analog Controller (legacy)

We describe the C1 as a Controller because it is more, much more than just a digital to analog converter. While creating a world-class DAC could be considered a sufficient challenge on its own, 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.

“Neutral, exciting, fast, tons of detail, yet musical in a way that is honest to the source, not gussied up with bloom and decay trails, it is not like the audio we grew up with. This kind of sound did not exist until now. As far as I’m concerned, CH Precision is at the forefront of digital technology. They are the leader of the pack.”

MARSHALL NACK, POSITIVE-FEEDBACK

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C1 Digital to Analog Controller

Of course, it is digital conversion that lies at the heart of the C1. The perfect preservation of time and amplitude information is critical to reproducing musical signals stored in digital format. Noise and jitter performance is central to the design of any high-performance DAC, but at CH Precision we believe that the solutions we have adopted for the C1 take digital performance to a whole new level. We have paid extraordinary attention to the master clock arrangements (as well as providing highly developed clocksync and external reference clock options) to minimize timing error to unprecedented levels, while our proprietary Polynomial Equations to Enhance Resolution (CH-PEtER) processing delivers incredible sample-to-sample resolution.

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 DSD, offering the ideal interconnection to the D1 CD/SACD Transport or other CH-Link HD equipped units
Standard digital inputs accept PCM to 24bit/192kHz, DSD 1bit/2.822MHz (DSD64)

Optional Digital Inputs

The C1 can accept up to three digital input boards to allow multiple digital sources to be connected
Ethernet audio streaming input board, UPnP/DLNA compatible, allows connection to audio servers (NAS drives), streaming services and internet radio
PCM to 32bit/38 kHz
DSD 1bit/2.8224MHz (DSD64), 5.6448MHz (DSD128) or 11.2896 MHz (DSD256)
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 input board – PCM to 24bit/384kHz, DSD 1bit/5.6448MHz (DSD128, DoP encoded)

Digital to Analog Conversion

Four PCM1704 R-2R converters per channel
Fully complementary, dual mono symmetrical circuit topology
Discrete dedicated regulated linear power supplies for low noise and maximum channel separation

Processing

Independent 2.4GFLOPS DSP engines for each channel
Proprietary CH-PEtER synchronous data over-sampling processing
DSD to 705.6kHz PCM conversion
Resolution enhancement of audio material recorded at less than 24bits
Digital to Analog converters data scrambling
Linearization of the R-2R converters through on-board calibration process

Timing & Clocking

Ultra low jitter digitally controlled VCXO oscillators with dedicated power supplies
Optional master/slave Clock-Sync board allows synchronization with external clocks when used with the D1 CD/SACD transport, I1 Universal Integrated amplifier or computer-based audio source
Clock-Sync board also allows use of the T1 10MHz Time Reference clock

Volume Control

By-passable 0.5dB step hybrid volume control, coarse steps using relays and a resistor ladder and fine steps in the digital domain, to maximise system resolution

Analog Input Board

Discrete, fully differential analog input circuit
Balanced XLR and single-ended RCA inputs
6V RMS maximum input level
Input offset and balance user selectable

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 RMS maximum output (balanced XLR), 2.7V RMS maximum output (single-ended RCA/BNC)
Switchable absolute phase
Channel balance in 0.5dB steps