May 2023 Eurorack round-up
This month’s best new modules include simple but effective VCOs, channel strips and compressors from the likes of Bocuma Sound Electronics, Feedback Modules and Erica Synths.
Erica Synths Stereo Compressor
The ever-reliable Erica Synths churn out a steady stream of quality Eurorack releases and this month is no exception. Primarily intended for drums, the Stereo Comp is a VCA compressor based on similar THAT chips to those used in classics like the SSL buss compressor. The Stereo Comp has a user-friendly interface which is much simpler than most studio compressors, based around just four controls. Input level and make-up gain are self-explanatory, but where you might normally expect to find controls for ratio, attack and release times, there are just two knobs, Threshold and Compression Amount. Despite not having the surgical precision of more complex compressors, the Erica design proves effective on all kinds of signals, with the obvious applications being stereo sub-mixes and drum busses.
The module can be operated in Stereo Link or standard dual mono modes, with the difference being that Stereo Link merges the sidechain inputs of the two level detection circuits. In regular dual mono mode, the level detection circuits are decoupled and operate independently, with the added benefit of external sidechain inputs to make things even more flexible (although, of course, the Threshold and Compression Amount settings must be identical for both channels). Sonically, you can achieve everything from subtle glue to extreme pumping effects. In use, the Stereo Comp feels reminiscent of VCA classics like the similarly user-friendly DBX 160A: quick to set up, versatile, with quality sound and excellent value at just under £175.
Feedback Pre BX
Feedback’s Pre BX is another one which you could file under the ‘simple but effective’ category. It’s a straightforward channel strip based on the sound of the Boss BX series of mixers released in the 1980s. Produced by Roland, the BX mixers have become cult classics in recent years for the colour and vibe they add to synths and drum machines. The Pre BX replicates that character with just three controls: gain to push the circuit into warm, fuzzy saturation and broad strokes two-band EQ. No frills, no fuss, no CV control, just excellent vintage character for less than £65.
Bocuma Sum0
Straight out of Guadalajara, Bocuma’s Sum0 is a keenly priced VCO with some nice workflow features. In terms of the basic setup, it’s a very nice oscillator with four independent outputs for the sine, pulse, triangle and sawtooth waves, plus FM, PWM and sync options. All of which is fairly standard stuff, but the main focus here is on harmonic summing, with a built-in mixer to combine the three harmonically rich waveforms plus an external signal. It’s particularly effective when combined with modulation from the built-in LFO, allowing you to mix and blend shifting harmonics as well as getting freaky by cranking the LFO up to audio rates.
Recovery Sound Destruction Device
Based on the guitar pedal of the same name, Recovery’s Sound Destruction Device combines variable resistor distortion with a twin T-notch filter. An unusual quirk here is that the controls are just labelled A, B, C, D, E and F and there’s no manual available yet. Based on the pedal, those controls would seem to be Gate, Compress, Destroy, Oscillate, Filter 1 and Filter 2. A single CV input allows you to modulate three of the parameters simultaneously, although once again it’s not clear which parameters these are. Do you really need to know? Maybe not. Even without being sure what you’re doing, the Sound Destruction Device does exactly that, from nasty clipping to more subtle filtering effects. Slightly opaque, but a lot of fun.
Blukač Endless Processor
Blukač’s Endless Processor falls somewhere between a looper and a granular processor, although both those descriptions undersell it a bit. Blukač describe it as a “dual-channel infinite sound sustainer machine”, taking an input signal and extending it forever, resynthesising and stacking up to five layers of sound on top of each other per channel. This kind of module can easily be intimidating but the Endless Processor’s approach is pleasingly intuitive, allowing you to select a channel and layer then use the Memory control to select the sample length and hitting the Infinity button to start the looping/sustaining process. It’s a relatively simple process, but one which quickly opens up interesting creative avenues, from building intense drones and complex synth timbres, through to stacking notes to create harmonies and chords.
Ritual Electronics Amnis
Finally this month, Ritual Electronics’s Amnis is a versatile digital shift register module with a few nice touches. The entirely knobless/switchless design requires just a clock input and a Data signal (any audio or CV) to generate eight gate outputs and four CV outs (three stepped, one slewed). Like most shift registers, it’s a very open-ended design which allows you to use it in all sorts of ways, from a modulation source to a sequencer or randomness generator. You get out what you put in with shift registers, almost literally. At just 6HP, the Amnis is a creative little tool to have in your case.
Greg Scarth