Oscillator Node

The Oscillator Node is an oscillator based synthesizer, which generates sounds using basic periodic waves (such as sine or sawtooth). It features built-it ADSR processing, and a detunable, stereo unison effect. It’s the fundamental component of most synth setups. Use it to generate a single controllable tone, or play notes from a source melody instead.


How to Use

The Oscillator Node is an audio source, and has 3 modes, configurable in properties. In Frequency Controlled mode, it outputs a single tone when you play your project. In the other 2 modes (Melody Controlled/Triggered), it outputs a single tone for each note in the connected melody input.

Connect the audio output to an Audio Destination Node to listen to the results.


Inputs

Melody Input

A Melody input to control the Node. This input is only available in Melody controlled mode.

The Oscillator Node plays a sound for each note in the source Melody, applying ADSR and frequency on a per-note basis, with unlimited polyphony.

Frequency-Control Input

A Control input to automate the Frequency setting, in Hz, from 0+ Hz to the Nyquist frequency. You can toggle this input from the Node properties panel, or by connecting to it. This is only available in Frequency controlled mode.

Detune-Control Input

A Control input to automate the Detune setting, in cents. You can enable this input from the Node properties panel, or by connecting to it.


Settings

Wave Type

The generated waveform type. Note that Custom: Organ and Custom: Horn are deprecated, but without an alternative as of yet.

Mode

Sets how the Oscillator Node generates sounds:

  • Frequency controlled: plays a single tone when playing the project, with its frequency set by the Frequency setting.
  • Melody controlled: enables the Melody Input, and plays each note in the connected melody. This mode has unlimited polyphony, that is, it can play an unlimited number of parallel notes at once. Live notes (e.g. those from a MIDI Keyboard Node) are played even without playback going.
  • Frequency controlled + melody triggered: same as Melody controlled, i.e. notes from the connected source melody are played, except the frequency of each note is set (overridden) by the Frequency setting.
Frequency

When the Mode setting is Frequency controlled or Frequency controlled + melody triggered, sets the fundamental frequency of the output, in hertz. Changes to this setting apply to the output waveform in real time, and you can also control it from the Frequency-Control Input.

Detune

Applies additional detune to the generated waveform, in cents, on top of the fundamental frequency. Unlike the Frequency setting, Detune is available in all 3 modes.

Unison Detune

When the Unison setting is enabled (see below), the Unison Detune setting replaces the Detune setting.

Additional voices added by the Unison setting are spread between the fundamental frequency, and the Unison Detune. For example, if Unison is set to 2 (meaning 3 voices total), one voice will not be detuned at all, one voice will be detuned by 50% of the Unison Detune, and the 3rd voice will be detuned exactly by the Unison Detune amount.

Unison

When greater than zero, adds additional voices to the output.

By itself, this setting doesn’t do anything audible. However, if you also set Unison Delay and/or Unison Detune to non-zero, the additional voices will start spreading out either by frequency, or timing, producing rich, dense synth sounds.

Higher values add more voices and enrichen the generated sound even more, but also need additional processing power. A high value with lots of notes playing at once is especially expensive. Try reducing the value if you encounter glitching.

Unison Stereo

Spreads additional voices added by unison between the left and right channels.

Unison Delay

Spreads additional voices added by unison in time, evenly, causing some voices to be very slightly delayed on a waveform level.

This setting is most noticeable with a zero Unison Detune setting, where it adds subtle, but interesting overtones to the generated sound. It’s usually inaudible with higher Unison Detune values.

ADSR

The Oscillator Node applies an ADSR (Attack-Decay-Sustain-Release) envelope to each sound played, configurable through a visual editor. See ADSR Envelope Editor for more details.


Outputs

Audio Output

The generated audio signal.


Technical Details

  • For all wave types except Sine, the Oscillator Node outputs a band-limited signal, which is not mathematically accurate.
  • Increasing the Unison setting gradually lowers the volume of individual voices, thus the output volume remains roughly the same.
  • While Unison is enabled, setting Detune to a non-0 value, and then setting it back to 0 will cause phases to potentially remain out of sync until the next tone played.

Similar Nodes

  • The Chorus Node can produce an effect very similar to the Unison setting with a non-0 Detune setting.
  • The LFO Node also outputs an oscillator-based periodic waveform – however, it’s more geared towards controlling other Nodes, rather than producing sounds on its own.
  • The Sin Node and Cos Node in the math category also output a sine wave.
  • The Timer Node, together with the Fractional Node, can also output a sawtooth wave, but without any band limiting.