I1 Universal Integrated Amplifier

The I1 integrated amplifier is possibly the most complex project that CH Precision has ever undertaken – and the most versatile product we have ever produced. Imagine the core qualities and capabilities of the C1.2 DAC Controller and A1.5 Amplifier combined in a single box. Now throw in the choice parts of the L1 Line-stage and add the option of a P1 phono-stage, all combined in a single, standard CH chassis and you begin to get the picture.

“A (very) few integrateds can match (the I1) in one area or another, but I know of nothing with a comparable combination of pedigree, versatility, footprint, expandability, upgradability, value, and world-class sonics.”

Alan Taffel, The Absolute Sound

Product Description

The I1 is supplied in standard form equipped with four digital inputs (CH-Link HD, AES/EBU, S/PDIF and TosLink – although a second identical digital input board can be added in the spare chassis slot if you need the extra connections) one set of balanced and two pairs of single-ended analog inputs. The factory fitted Ethernet Control Board, which allows the unit to be remotely accessed, configured and controlled via the CH-Control Android App, can be replaced with a full network streaming capable Ethernet input and a separate, asynchronous USB input card can be added to enable connection of computer sources for file replay. All digital inputs are fully MQA compatible, while our latest proprietary, fixed-point PEtER spline filtering and updated DSP deliver accurate and musically natural digital decoding. The discrete, fully-complementary analog input boards can be fitted with additional internal circuit blocks that allow owners to convert either or both of the RCA analog inputs into current-sensing MC phono-inputs, complete with switchable replay EQ settings for RIAA, eRIAA, Decca, Columbia, EMI and Teldec (DGG) curves.

Finally, a Clock- Sync board allows you to slave the I1 to external master clocks, or designate its internal clock as the system master. Dominating the interior of the I1 chassis, you’ll find a massive 1000VA transformer that’s more than capable of supporting the 100 watt/channel into 8 Ohms rated output; in combination with the 100,000uF of reservoir capacitance it allows the output stage to handle awkward loudspeaker loads with ease.

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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 D1.5 CD/SACD Transport or other CH-Link HD equipped units
  • Standard digital inputs accept PCM to 24bit/192kHz, DSD 1bit/2.822MHz (DSD64 DoP encoded)
  • Ethernet Control Board (replaced by the network streaming board if ordered or retro-fitted)

Optional Digital Inputs

  • The I1 can accept two digital input boards, allowing multiple digital sources to be connected. The second board can be either another standard Digital Input Board or the USB Input Board
  • Ethernet audio streaming input board, UPnP/DLNA compatible, allows connection to audio servers (NAS drives), streaming services or internet radio
  • PCM to 24bit/384kHz
  • 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

  • Individual Multi-bit Delta-Sigma converters for each channel
  • Fully complementary, dual mono symmetrical circuit topology
  • Discrete dedicated, shunt topology regulated linear power supplies for low noise and maximum channel separation

Processing And Clocking

  • Proprietary CH-PEtER 32-bit fixed point spline filter, synchronous data over-sampling processing
  • Resolution enhancement of audio material recorded at less than 24bits
  • Full MQA decoding (unfolding and rendering) at 24bit/352.8 – 384kHz on all inputs.
  • Two ultra low jitter VCXO oscillators, one per time domain
  • Optional master/slave Clock-Sync board allows synchronization with external clocks or when used with the D1 CD/SACD transport
  • Clock-Sync board also allows use of the T1 10MHz Time Reference clock


  • 480 x 272 pixel, 24bit RGB AMOLED
  • 15 standard, user-selectable text colors
  • User definable RGB option for text color

Remote Control Options

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

Technical Specification

Max analog input level
8V RMS balanced
4V RMS single-ended

Input impedance
94kΩ or 600Ω balanced, 47kΩ or 300Ω single-ended

A/D conversion
DXD 24 bit / 384kHz direct conversion

Phono MC current-sensing input impedance
< 100mΩ, virtual ground

Playback EQ curves accuracy
+/- 0.01dB (software implementation)

Post volume control analog line outputs max level
4V RMS balanced

Loudspeaker outputs
2x 100W RMS/8Ω
2x 175W RMS/4Ω

440 x 440 x 133mm (W x D x H), 33kg

I1 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.