ADDAC 107 Acid Source review

We take on ADDAC’s latest compact synth voice

  • £199
  • €210
  • $216
ADDAC Systems 107 Acid Source
(Image: © ADDAC Systems)

MusicRadar Verdict

Typical ADDAC attention to detail makes this a fantastic option for anybody looking for a small, all-in-one voice that plays well with others.


  • +

    Versatile tonal options.

  • +

    Compact size for functionality.

  • +

    Excellent build quality.


  • -

    Limited VCA control.

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ADDAC 107 Acid Source: What is it?

Synth voices are easy to find and come in all shapes and sizes, but to find one that offers a complete palette, that is well built and comes in a suitable form factor can be much harder – even more so when looking for consistency and personality in one module. ADDAC aims to make this a simple choice with the release of the Acid Source.

As with all ADDAC modules, the hardware is solid, well built and clearly labelled. While a cursory glance may make it appear a little utilitarian compared to some of the wild graphics and glyphs seen elsewhere, the clean and clear approach makes navigating in a darker environment that much simpler.

For a module that has so much on offer, ADDAC has done a great job of keeping things compact, too. The Acid Source is just 9hp wide and 40mm deep, keeping it suitable for all manner of cases and skiffs.

ADDAC Systems 107 Acid Source

(Image credit: ADDAC Systems)

ADDAC 107 Acid Source: Performance and verdict

The main task of the module is to generate tones, of which many can be coaxed, from simple square to more complex output, when combined with a saw tooth or triangle, each of which can be blended in with a pot. Controls for frequency and fine-tuning both live up top in this section. Passing on to a beautiful sounding filter, with low, band and high-pass modes and a resonance control. This filter sounds smooth but juicy, with lots of character and can be controlled by CV, as can pitch and the decay of the onboard VCA. Yes, this synth voice has a VCA built in, adding a certain amount of versatility, while freeing up other areas of a patch for other duties. That said the VCA only has a decay control, rather than a full envelope. However, that is part of the joy of this module, as it can be controlled by any external input. This encourages some experimentation, which can be quite the journey, as you look for ways to control the squelch of the filter. It’s an uncommonly rewarding process, and one that ADDAC has implemented well.

Interestingly there is also an accent CV input. This is common on drum modules but rarely seen elsewhere, and enables the VCA to have triggered boosts, adding further levels of personality and musicality to a patch. Modules that have features like this can really add some movement and feel into your music, so thanks to ADDAC’s developers for including it.

For some additional control there is also a gain control for external inputs, which allows for greater than standard voltages (up to 10v, rather than 5v), lending themselves to some lovely aggressive distortion. 

All in all, this is a great sounding, compact synth voice. It lends itself to bass and lead tones with the possibility for some extra grit and growl you will find it hard to find elsewhere. 

MusicRadar verdict: Typical ADDAC attention to detail makes this a fantastic option for anybody looking for a small, all-in-one voice that plays well with others.

ADDAC 107 Acid Source: Hands-on demos



ADDAC 107 Acid Source: Specifications

  • KEY FEATURES I/O: Complete synth voice, Includes multi mode filter, External gain control.