Reads live audio, or the song on the timeline's audio track, and outputs it as a signal you can patch into anything. Three modes give you different ways to read the audio: overall loudness, frequency spectrum, or raw waveform shape.
Inputs
Port
Type
Default
Range
Description
Gain
Scalar
1.0
0–4
Amplifies the audio signal before output
Freq Low
Scalar
20
20–20000
Low frequency bound for spectrum mode
Freq High
Scalar
20000
20–20000
High frequency bound for spectrum mode
Outputs
Port
Type
Description
Out
Scalar
Audio signal; meaning depends on the selected mode
Controls
Mode: Loudness (single level value), Spectrum (the frequency spectrum, swept across the frame from Freq Low to Freq High), or Waveform (the amplitude shape of the audio, always 0 or above).
Channel: Which audio input channel Waveform mode reads. Loudness follows the loudest channel, and Spectrum analyzes a mix of all channels.
Fall: Envelope decay time in seconds for Loudness and Spectrum modes. Short values snap to transients; longer values smooth them out.
Window: In Waveform mode, replaces Fall. How much recent audio, from 5 to 3000 ms, is spread across the frame.
Ideas
Waveform into Parametric Curve Y + Phasor into From Polar: projects the audio waveform onto a circle, creating a reactive ring that pulses with the music.
Spectrum mode into a Color node's hue: along the path, each point's hue follows the level of its slice of the spectrum, so the colors ripple with the music.
Loudness into any shape's scale: bass-pumping geometry that grows on every kick.
Tips
In Spectrum mode the output sweeps from Freq Low to Freq High along the frame. Inputs that read a value per point (a Parametric Curve's Y, Colorize's Color) see the whole band. Inputs read once per frame (Brightness, Duplicator Amount) see only the Freq Low bin, so set Freq Low to the frequency you want to follow.
Waveform mode samples the audio buffer per point across the frame. The signal is rectified (always 0 or above), so you get the amplitude contour of the wave, not a signed scope trace.
The node reads the audio source selected in Settings → Devices (an input device or Timeline audio track) and outputs 0 when none is selected. See Audio-reactive visuals for setup.
Gain applies before output. Use it to boost quiet sources or tame loud ones.
Related
Envelope: shape audio-triggered hits with attack/decay control
Parametric Curve: wire audio signals into position for reactive shapes