Frap Tools CGM Insert: Expanding Eurorack Mixer Connectivity with Stereo FX

Since 2016, the CGM mixer family from Frap Tools has steadily grown into a staple of Eurorack mixing, but even with its flexible architecture, users have long requested a more elegant way to integrate stereo effects. The new Insert module, affectionately dubbed the ‘I’ in the CGM lineup, directly answers this demand by allowing both series and parallel connections of stereo effects within the CGM ecosystem.

The Insert module is designed as an add-on that can be patched between any two points in the CGM summing bus. Whether you want to insert a compressor at the end of your mix or run a reverb in parallel to glue things together, the Insert makes it possible. This approach not only expands the creative palette for modular mixers but also reflects Frap Tools’ willingness to listen to its user community, as the module’s conception was driven by suggestions from their Discord server.

At its core, the Insert module features two pairs of stereo inputs and outputs, each with its own dedicated gain switches. The first pair forms the Insert circuit, which completely replaces the internal CGM signal path at the chosen point, while the second pair operates as a parallel circuit, summing external effects back into the mix.

The gain switches on both input and output sides offer three levels of attenuation or amplification, allowing precise control over signal levels. This means you can balance modular-level signals with outboard gear or compensate for devices lacking make-up gain. The flexibility here is crucial for maintaining unity gain or intentionally boosting or cutting signals, ensuring the Insert adapts to a wide range of effect processors and patching scenarios.

One of the Insert module’s standout features is its routing flexibility. It can be placed between a group and the master, between groups, between channels and groups, between channels, or even directly between a channel and the master—no group required. This modular approach means you can target specific sections of your mix for processing or create subgroups with their own dedicated effects.

Throughout the video, Frap Tools demonstrate each of these connection types, showing how the Insert can serve as an end-of-chain effect point, a subgroup processor, or a creative parallel effects send. The ability to move the Insert to different positions in the signal path is a boon for patch-oriented users who want to experiment with dynamic signal flows and custom mixing architectures.

Frap Tools have ensured that the Insert module plays nicely with every member of the CGM family, including discontinued units. The module ships with two dedicated Insert cables, designed to handle the necessary connections between modules—whether you’re patching between channels, groups, or the master. The video provides a step-by-step installation guide, covering various scenarios and highlighting the importance of correct cable orientation and power management. For more complex setups, additional link cables are available, but the included pair will cover most needs. This attention to compatibility and modularity cements the Insert as an essential utility for anyone looking to expand their CGM-based sound design or live mixing arsenal.