Controller: LFO

Patch Category: 
Controller
Patch Name: 
LFO
Patch First Appeared in Version: 
10.4 (Tiger)
Patch Execution Mode: 
Processor
Patch Description: 

The LFO (Low Frequency Oscillator) patch is used to generate a repeating sequence or waveform, which is useful for animating other patches. It outputs a number.

It is possible to modify the Timebase for this patch.

Patch Inputs: 

Type: What type of pattern to generate.

  • Sin - a smooth wave
  • Cos - like sin, but with opposite phase.
  • Triangle - like sin/cos but with sharp corners, so motion will not be smooth
  • Square - a binary type pattern. The output will alternate between the highest and lowest value. Useful for turning things on and off, blinking lights etc.
  • Sawtooth (up or down) - moves steadily from low to high value (or vice versa) then resets to the low value. Useful for example for moving something repeatedly across the screen in one direction.
  • PWM - similar to Square, but you have control of the ratio of time spent at each end of the range using the PWM input to create short or long regular pulses.
  • Random - outputs a random number from the range. The number will change at the end of each period.

Period: The period of time that one cycle of the sequence will take, in seconds. For example a Sin output with a period of 3 will take 3 seconds to go from the initial medium value to the high value, down to low, and return to medium.

Phase: This controls the phase of the waveform (effectively if shifts the waveform in time, so the cycle will start later or earlier). The units are Degrees, so the effective range is 0 - 360. A value of 180 is equivalent to a 50% offset, so an LFO with a period of 10 seconds and a phase of 180 is the same as an LFO with a period of 10 seconds that starts 5 seconds late. A Sin wave with a phase of 90 is the same as a Cos wave with a phase of 0.

Amplitude: This sets the 'height' of the wave, or the difference between the lowest and highest value.

Offset: This sets the 'middle value' of the range. For example, an LFO with an amplitude of 1 and an offset of 0 will produce values in the range -0.5 to 0.5, while one with an amplitude of 5 and an offset of 5 will produce the range 0 to 10.

PWM Ratio: The only has an effect with the PWM type. It controls the ratio between the high and low value. A low PWM ratio will produce a short pulse with a long pause, and a high ratio will produce a long pulse and a short pause.