A polarizer, often referred to as an attenuverter or bipolar attenuator, is a module or a function within a module that is used to control the amplitude and polarity of an input signal, typically a control voltage (CV) signal. It allows you to adjust the signal level and invert the signal if needed.
A polarizer typically has an input jack for the signal you want to process, a knob or slider to adjust the attenuation and inversion, and an output jack for the resulting signal. When the knob or slider is at its center position, the output signal is zero or effectively muted. As you turn the knob clockwise from the center, the output signal increases in amplitude, maintaining the same polarity as the input signal. As you turn the knob counterclockwise from the center, the output signal also increases in amplitude but with the opposite polarity (inverted) compared to the input signal.
Polarizers can be useful for various purposes in a modular synthesizer patch, such as:
- Adjusting modulation depth: By controlling the amplitude of a modulation source, you can fine-tune the impact of the modulation on the target parameter.
- Inverting modulation signals: Inverting a modulation signal can create opposite or complementary modulation effects.
- Creating complex modulation shapes: By combining inverted and non-inverted modulation signals, you can generate more intricate modulation patterns.