So… We started our monthly Modular feature last year and it sort of crashed and burned until now. As we reboot the series, I want to do so with one of the super star modules of my eurorack modular rig.

ES-3 Lightpipe/CV Interface

es-3mk3-334x1024The Expert Sleepers ES-3 is one of the most important modules in my euroack modular synth system. In today’s hybrid world of analog and digital integration it’s all about integration. Rocking your modular synth with Blocks or Softube Modular software eurorack platforms require tools like Expert Sleepers ES-3 module to get the job done.

The Expert Sleepers ES-3 module allows you to take up to 8 CV or audio signals from your computer / DAW into your euroack modular system via your audio interface. I can’t stress enough how huge that is.  The result of having 8 CV or audio signals via ADAT cable into your favorite DAW  means that you can do things like modulate your hardware modules with your software modules easily. The Expert Sleepers ES-3 module is the bridge between your hardware and software modular worlds making easy work out of what would otherwise be a very tedious and less than ideal task.

Expert Sleepers describes the ES-3 as “a Eurorack format module which converts eight channels of ADAT Lightpipe input to DC coupled outputs on 3.5mm jacks, for the ultimate convenience in connection of a DAW directly to analogue synthesizers.”

The build is rather simple with an Adat input connection and 8  DC-coupled 3.5mm jacks.  Maximum output voltage is approximately ±10V DC, which is better than most audio interfaces that feature DC coupled i/o. Here you get the full range of output voltage. Each jack has two LEDs for output voltage activity.

The module is solid and the functionality is very straight forward.

I featured the ES-3 in episode 3 of the BBoyTech Modular Journal Series (Modular Journal Episode 3 – Expert Sleepers ES-3 – MPC Drums and Modular Processing). Take a look at the video to see a bit more on how the unit works to bridge the gap between DAW and eurorack.


  • Panel width: 8HP
  • Module depth: 53mm
  • Input connection: optical, ADAT Lightpipe standard
  • D/A conversion: 24 bit, 113dB SNR typical
  • Output connections: 8x 3.5mm jacks, DC-coupled
  • Maximum output voltage: approximately ±10V DC
  • Indicators: LED for ADAT clock sync; 2 LEDs per channel indicate output voltage (+ve/-ve)
  • Current draw*: 168mA on the +12V rail, 30mA on the -12V rail (198mA total)
  • takes Doepfer and Analogue Systems mounting holes (using a ‘slot’ rather than a single round hole).
  • power connector is a Doepfer standard 16 way IDC, with -12V furthest from the top of the board.
  • Current draw depends on sample rate and number of channels in use. Given figures are maximums (48kHz, all channels in use).

For more information head over to the Expert Sleepers ES-3 product page.

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