Expert Sleepers ES-3 review

A new approach to bridging the gap between CV synths and DAWs

  • £186
A fantastic new approach to controlling CV hardware.

MusicRadar Verdict

Silent Way could change the way we think about synths and the hardware makes it easy to integrate.


  • +

    Silent Way includes a range of CV generator plug-ins. Excellent integration of hardware and software. Incredible options for controlling modular synths.


  • -

    Can be complicated. Hardware option isn't as good value as the software alone.

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For a one-man company, Expert Sleepers has certainly been busy over the last few years. Not content with creating leftfield plug-ins such as the Augustus Loop delay and excellent Minky Starshine additive synth, Andrew Ostler has turned his hand to revolutionising the way we integrate CV-controlled synths with our DAWs.

The Silent Way plug-in suite essentially consists of utilities for generating control signals to be sent to analogue synths, but it goes way beyond the typical CV and gate features of most hardware alternatives.

"Silent Way opens up sound design options that'd be expensive, difficult or impossible any other way."

Not only does the software offer options that owners of traditional MIDI-to-CV converters can only dream of, but Expert Sleepers' own range of Eurorack format modules offer input and output options to suit everyone.

So, armed with a couple of pre-MIDI analogue synths and a stack of modular goodies, we set about seeing what it could do.

In a Silent Way

The heart of the product range is the Silent Way software plug-in suite, available for Mac (AU and VST) and PC (VST). Following hot on the heels of MOTU's Volta software, the concept is remarkably simple, allowing you to generate control voltages in your DAW and send them to analogue synths, modular setups or CV-controlled effects via your audio interface.

The ability to sequence CV synths is a selling point in itself, but Silent Way offers so much more than just basic MIDI-to-CV conversion. However, before we start using the software there are a couple of hardware questions we need to answer.

Since most audio interfaces block DC voltages at their outputs, Silent Way is picky about which hardware can be used straight out of the box (a full list of compatible interfaces is available on Expert Sleepers' website).

Alternatively, Silent Way's AC Encoder plug-in avoids the need for DC-coupled outputs but requires a bit of DIY work to convert the signal back into DC for your synths.

If you're not confident following the instructions to wire up cables or passive breakout boxes with built-in rectifiers, Expert Sleepers offer the ES-1 module, an active breakout box in Eurorack format which converts up to eight analogue outputs into DC control voltages suitable for your synths. It'll set you back £131 with DSUB input or £143 with quarter-inch jacks.

However, we decided to test the new ES-3 module, which works on the same principle as the ES-1 but accepts an ADAT lightpipe digital input rather than analogue signals.

For those of us with a spare ADAT output on our interface, the ES-3 is almost certainly more convenient than tying up eight analogue outputs. It's also one of the most friendly plug-and-play pieces of hardware you'll ever have the pleasure to use.

Simply hook up the Eurorack power cable, connect the Lightpipe input and everything works. If only all hardware was so simple.

Remote control

So, with the outputs sorted, it's time to get started with the software. Silent Way includes a total of 11 plug-ins that offer everything from the most simple DC voltage generators to complex options which will have you thinking about the potential of your analogue gear in entirely new ways.

The Voice Controller is one of the more advanced plug-ins but it's also where most of us will probably start, allowing our DAWs to generate CV and gate control signals from a MIDI note input.

The initial tuning process demonstrates Silent Way's straightforward, logical approach to integrating software and hardware: connect the plug-in's CV output to your synth, route the output audio signal back to the plug-in's input and then hit one of the calibration buttons, either for the standard V/Oct mode or the less common Hz/V system depending on the unit to be tuned.

The plug-in automatically sends a CV sweep to your VCO, analyses the frequency of the resulting signal and generates a calibrated tuning setup in just a few seconds.

We tested Silent Way with a Roland SH-101, Korg MS-10 and a selection of modules and found tuning to be fast and trouble-free. In addition to the basic note and gate signals, Voice Controller also outputs three multi-stage envelopes, a trigger pulse and a velocity CV, with all of the signals routed to six different outputs via a matrix mixer panel.

Complete control

Expert Sleepers can even generate polyphonic CV outputs for controlling multi-voice synths. Converting directly from sequenced notes to CV and gate without an intermediate MIDI stage ensures that timing is rock solid and there are no digital quantisation issues.

In a modular setup, the Voice Controller plug-in alone could probably replace a dozen or more modules.

Other plug-ins on offer include the self-explanatory LFO, with options way in excess of anything we've ever come across in the analogue world, and the Step LFO which allows CV values to be sequenced in tempo-synced steps.

Plug-ins can also be chained together, so by running the output of the Step LFO to the Quantizer it's possible to tune the LFO's pitch output to pre-defined musical scales or turn a smooth LFO triangle wave into a jagged digital staircase. The potential to get creative is massive.

Some of the plug-ins offer a huge range of controls to fiddle with, but the well-designed software remains easy to use if all you want to do is access the basic features.

For those who want to dig deeper, the documentation is also excellent, explaining every part of the setup process and each aspect of operation in clear steps.

Owners of pre-MIDI analogue synths are sure to be attracted to Silent Way's Voice Controller options, but semi-modular or modular synth owners will benefit the most from the more advanced features, as will owners of CV-controlled effects such as MoogerFoogers.

If you've got a DC-coupled interface and some CV hardware, Silent Way is a no-brainer at just £32. The voice control features alone may not quite justify the expense of investing in the Expert Sleepers hardware, but the price does compare favourably to a multi-channel MIDI-to-CV converter.

However, if you've got a modular synth to take advantage of the more advanced features, Silent Way and an ES-1 or ES-3 starts to look like a real bargain. With the Eurorack format becoming more popular, cases and power supplies are easily available and we're sure quite a few people will be tempted into getting started with modular hardware thanks to Expert Sleepers.

Silent Way opens up control options and sound design possibilities that would be expensive, difficult or even impossible to achieve any other way. It's a fantastic new approach to controlling analogue Control Voltage hardware.

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