Use attenuation to control the level of a CV signal
Let’s dive deeper into semi- and full-modular techniques. Again, using the MiniBrute 2 as an example, if we patch LFO 1’s output into the Filter Cutoff input, we break the prewired ‘LFO to pitch’ connection, and we can now modulate that filter frequency with the LFO. Simple! However, unlike regular mod matrix patching, we have no control over the amount or depth of modulation – the LFO is constantly at max strength. Handily, this is where CV attenuation comes into play, which can be used as an intermediary ‘level amount’. Patch the LFO’s output into an attenuator’s input, then patch the attenuator’s output into that Cutoff input. Voila: you can now twist the Attenuator knob to increase or decrease the LFO’s influence over cutoff modulation. Attenuation is useful for controlling the level of any CV signal, which is why most semi-modular synths feature at least one, and why many modular obsessives own at least one dedicated attenuator module for controlling levels.
The problem here is that the LFO is sweeping the full range of pitch up and down, and there’s no way to dial this back. So instead, we patch the LFO Out into the Att 1 Input, then grab another cable and patch Att 1 Out into the Osc 1+2 Input.
In this example, we’re using the Behringer Neutron. Over on the patchbay, the synth’s LFO output is plugged into the Osc 1+2 Input, meaning the LFO is modulating the pitch of both oscillators.
Now we can use the Attenuator 1 knob on the interface as an ‘amount’ or ‘mix’ control to govern the amount of LFO modulation – we’ll pull this knob back to reduce this pitch modulation.