Building Blocks


There are several effect “modules” that can be used and combined in a pedal.



Each module name has an fx_ prefix such as fx_delay and fx_phaser. A sketch can contain multiple “instances” of a module and multiple modes.



Each module also has a combination of audio nodes and control nodes. More complete documentation for each module can be found in the cheatsheet, a lighter weight reference, or the full API documentation. Both of these are available on API Documentation page in the menu above.



Below is a brief summary of the available modules:



  • fx_adsr_envelope - An “envelope” or volume control functon that determines how the volume of a signal changes over time after a new note/pluck is detected. ADSR stands for Attack, Decay, Sustain, Release. Here’s a nice video explaining the basics of ADSRs: https://www.youtube.com/watch?v=JT6rixgu4s4. The ADSR can also control things other than volume. For example, it could be connected to a filter to sweep the filter over the incoming instrument signal.
  • fx_amplitude_modulator - Varies the volume of the signal over time using a low frequency oscillator (LFO). Amplitude modulation is what creates the tremelo sound (varying the volume of an instrument signal using a sine wave function).
  • fx_biquad_filter - Provides various common types of audio filters such as low-pass, high-pass, band-pass, parametric and several others. Audio filters can be static (not changing) or dynamic (changing). The frequency and resonance of a filter can be tied to several different types of control sources such as pot on the pedal, or an oscillator, or the volume of the incoming signal.
  • fx_compressor - Provides “dynamic” gain control. In essence when the volume of the incoming signal exceeds a threshold, the compressor will dynamically adjust the volume down. It can create long sustaining sounds rather than a pluck followed by a quickly diminishing signal. Here is a nice video explaining the basics of compression: https://www.youtube.com/embed/8nM5GsNNbyA.
  • fx_delay - A basic echo effect with lots of adjustable parameters and a send/receive loop to inject additional effects into the echo loop.
  • fx_destructor - A variety of distortion functions including soft, polynomial tube-amp-like distortion, fuzz, bit-crushing, sample-rate crushing, shaping, digital distortion and more.
  • fx_envelope_tracker - An input-only module that tracks the volume of the incoming signal. Its control output can be connected to other modules to create dynamic, volume controlled effects like envelope filters and auto-wahs.
  • fx_gain - A basic volume control element. This element is also useful when mixing between different branches of an effect or turning on/off different aspects of an effect.
  • fx_looper - A very flexible looper that supports variable playback rate and reverse playback. Multiple loopers can be used to create multi-layer loopers.
  • fx_mixer - A collection of mixer modules for mixing signals together. Presently available in 2->1, 3->1 and 4->1 configurations.
  • fx_octave - A synth octave generator that creates a synth note at the current frequncy, one octave down, and two octaves down. Synth mix and synth waveforms are configurable.
  • fx_oscillator - A collection of oscillators that can be used either for audio synthesis or control
  • fx_phase_shifter - A phase shifter
  • fx_pitch_shift - A pitch shifter
  • fx_ring_mod - A ring modulator / analog pitch shifter
  • fx_slicer - Rhymically sequences incoming audio through different effects. Great for creating interesting rhytmic effects.
  • fx_variable_delay - A super useful building block that can be used to create flange and chorus effects, vibrato, and general modulation. Fun to use in feedback loops and fx send/receive loops.