Sorry for the late reply. I am now finally back in front of my modular.
So both the Pitch (V/oct) custom control and the Linear custom control should be able to give you a full sweep of the LPF frequency.
Here is how I would set it up:
To sweep the frequency linearly:
- Assign a linear custom control
- Set the modulation gain to at least 1000x. The linear control goes from -5 to 5 so this gives you a sweep of -5kHz to 5kHz. If you want a wider range then you can set the modulation gain even higher.
- Set the modulation bias to taste. Here I am using about 2.5kHz.
To sweep the frequency exponentially there are no gains to set:
- Assign a pitch custom control
- Set the modulation bias (tune) to taste.
For completeness, at the Custom Unit, level my example looks like this: