Arturia Efx REFRACT

Arturia Efx REFRACT: Stunning new unison effect, free for a limited time

2023 has been a very fruitful year for anyone that is interested in quality free plugins. We’ve had some amazing shimmers like Adam Szabo’s Solaris, audio manipulation VST effects like Cymatics Deja Vu and plenty more freebies with actual commercial values.

Unison Powerhouse

The latest VST plugin effect that fits in that criteria quite well is Arturia’s new Efx REFRACT – a free unison-focused multi FX utility that is capable of advanced, multi dimensional effects.

(For general knowledge, the word or term “refract” (refraction) is a phenomenon in physics where waves (like light) transmit or pass through from one medium to another. In this case, Arturia’s VST plugin transmits sound waves from one effect – unison – to another)

In addition to its base unison capability, Arturia Efx REFRACT also serves as an harmonizer, advanced distortion module, coloring agent and sound shaping filter – all in conjunction with the base functionality.

The unison feature (labeled as Refraction) lets you choose the amount of voices or “dimensions” that you’d like to apply to the source sound – from 1 to 8 voices. After that, it passes the sound through an effect of your choosing – with the following listed options: Bandpass, Comb Filter, Bitcrusher, Distortion and Harmonizer.

Its harmonizer mode has varying possibilities – they go all the way from simple Major and Minor chord intervals to more complex modes. Efx REFRACT is able to produce rather clean harmonics, with no apparent audio artifacts.

The remaining parameter is LFO. The LFO parameter controls the behavior of the effect – starting with the type of soundwave, like Sine, Square, Triangle, Sawtooth, etc. It also controls the speed (rate) of the LFO effect, which you can of course sync to the host tempo. On the right side of the interface, you can control the LFO amount and on the opposite side the Refraction LFO amount.

So, aside from its technical capabilities which are indeed impressive, Efx REFRACT is also paired with a quite intriguing visual. I really like those dynamic, live animated 3D prism geometries, which act as audio visualizers.


To get Arturia Efx REFRACT, you may enter the Arturia official website and register. All downloads are done via the Arturia Software Center (ASC) – which is the Arturia application manager. The plugin supports 64-bit Windows and macOS (VST3, VST, AU, AAX and the NKS format).