Expert Sleepers ESX-8CV mk2 Expander Eurorack Module

The ESX-8CV is an expansion module for the ES-4, ES-40 or ES-5, adding eight CV outputs from one expansion header.

In order to squeeze eight 12 bit channels through one 8 bit connection, the channels are time-multiplexed and so effectively run at between one-third and one-twenty fourth of the audio sample rate. For example, if the audio interface/DAW is running at 48kHz, the ESX-8CV's outputs are running at between 16kHz and 2kHz, depending on how many channels are active. This is still plenty fast enough for most CV purposes, except for audio-rate modulation and the very fastest envelopes. Because the outputs are still derived from the audio stream, they retain the advantages of the ES-3/4 over traditional MIDI-based interfaces, that is, rock solid timing and absence of jitter.

The outputs are hardware calibrated and so do not require the use of e.g. Silent Way's software calibration when used with standard V/octave synths/oscillators. That said, the ESX-8CV's 12 bit resolution is adequate to perform software calibration if required (e.g. to cater for misbehaving oscillators that don't track well to a standard calibration), or to support oscillators with a Hz/V response.

The ESX-8CV's specifications are as follows:

• Panel width: 4HP
• Module depth: 49mm
• Digital input: connection from ES-4, ES-40 or ES-5 module
• Analogue outputs: 8x 3.5mm jacks, DC-coupled
• Output voltages: ±5.33V hardware calibrated, or ±9.5V uncalibrated (jumper setting)
• D/A conversion: 12 bit, using high precision Analog Devices DACs
• Indicators: illuminated jack sockets
• Current draw: 41mA on the +12V rail, 33mA on the -12V rail

The front panel is drilled for both Doepfer and Analogue Systems mounting holes (using a 'slot' rather than a single round hole). The power connector is a Doepfer standard 16 way IDC, with -12V furthest from the top of the board.

For more detail, please see the user manual.

ESX-8CV mk2

May 2017 sees the launch of the "ESX-8CV mk2". Functionally equivalent to the original ESX-8CV, the mk2 adds illuminated jack sockets, has reduced power consumption, and matches the look of the ES-8 and the other 2017 updates.

Software Requirements

The ESX-8CV requires software in order to time-multiplex the eight output signals, and to encode them for the ES-4 or ES-5. Currently, the only such software is the 'ESX-8CV Combiner' plug-in, part of Expert Sleepers Silent Way, and our Max/MSP external (see below).

Silent Way is available in AudioUnit, VST & AAX formats for Mac OS X and Windows. Use of Silent Way therefore requires a compatible host application (DAW). 

A Silent Way licence is not included with the ESX-8CV - however, the ESX-8CV Combiner plug-in functions in a licence-free mode, so ESX-8CV users are not forced to buy Silent Way. Such users can than evaluate the rest of the Silent Way suite in demo mode.

Max/MSP External

We provide an 'external' for Max/MSP to enable users of Max to easily integrate the ESX-8CV into their patchers. This can be downloaded from the downloads page.