Expert Sleepers Announces ES-4 SPDIF-to-CV Interface

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Expert Sleepers are proud to announce the latest addition to their line-up of Eurorack modules, the ES-4 S/PDIF / CV Interface.

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The ES-4

The ES-4 is a Eurorack format module which converts a standard S/PDIF input to five channels of control voltage.
Two of the five channels are calibrated to provide over 5 octaves of 1V/octave pitch CV. The remaining three channels are general purpose outputs (for use as e.g. gates, envelopes, LFOs) and each have a nominal range of 0-10V or ±5V (user selectable).

Since S/PDIF is a stereo-only format, the encoding of the five channels on to two is handled by software to be provided as part of Expert Sleepers Silent Way.

The ES-4 will connect to any audio device using the S/PDIF standard. This includes the digital audio output provided as standard on all recent Macs.

The ES-4 Gate Expander

The ES-4 Gate Expander is a Eurorack module which works in tandem with the ES-4 to offer 8 on/off outputs for use as gates, triggers, clocks etc.
Up to five ES-4 Gate Expanders can be attached to one ES-4 - one per ES-4 channel. (The 8 outputs of the Gate Expander reflect the 8 bits of CV information passed to the ES-4's DACs.) Therefore you can combine the modules to create a system with up to 40 independent gate outputs - all driven from a single S/PDIF connection.

ES-4 prelimiary specifications
Panel width: 8HP
Module depth: 51mm
Digital input: coaxial S/PDIF
Digital output: coaxial S/PDIF
Analogue outputs: 5x 3.5mm jacks, DC-coupled
Output voltages
Channels 1-2: 0-5.3V (when trimmed for 1V/octave response)
Channels 3-5: 0-10V or ±5V (jumper selectable per channel)
D/A conversion: 8 bit, using high precision Analog Devices DACs
Indicators: LED for S/PDIF sync lock; 2 LEDs per channel on channels 3-5 indicate output voltage (+ve/-ve)
5 headers for connecting ES-4 Gate Expander modules (see below)
Digital audio I/O header (I2S format) for future expansion
ES-4 Gate Expander preliminary specifications
Panel width: 4HP
Module depth: 24mm
Analogue outputs: 8x 3.5mm jacks, DC-coupled
Output voltages: 0V/5V or 0V/12V, selectable via jumper in groups independently for channels 1-4 and 5-8
Indicators: LED per channel
For more information, please see:

and watch the demo video: