Green Noise Generator (Golden Ratio LFO v1.2)

An Audacity Nyquist plugin that generates green noise with dynamic harmonic movement using golden ratio-based modulation.

Overview

This plugin generates green noise (a perceptually balanced noise between pink and brown noise) with sophisticated amplitude and frequency modulation driven by the golden ratio (φ ≈ 1.618). The result is an evolving, organic soundscape that avoids the static quality of traditional noise generators.

Features

• Customizable Noise Base: Choose between pink noise (-3dB/octave) or brown noise (-6dB/octave)
• Golden Ratio LFOs: Two independent low-frequency oscillators modulate the signal using:
  • AM LFO: Amplitude modulation at frequency speed × 1/φ for smooth rhythmic swells
  • Filter LFO: Resonant filter modulation at frequency speed × φ for dynamic tonal movement
• Resonant Bandpass Filter: Adds warmth and presence to the generated noise
• Automatic Normalization: Output normalized to -1.0 dB for consistent levels

Parameters

Parameter	Range	Default	Description
Duration (Minutes)	0.1–60	30.0	Length of generated audio
Base Slope	Pink (-3dB), Brown (-6dB)	Brown	Frequency response of noise floor
Lower Frequency (Hz)	100–1000	100	Bandpass filter lower cutoff
Upper Frequency (Hz)	200–2000	600	Bandpass filter upper cutoff
Modulation Speed (Hz)	0.001–2.0	0.001	LFO frequency scale factor
Modulation Depth	0.0–0.5	0.1	LFO amplitude (0 = no modulation)
Filter Resonance (Q)	0.1–5.0	0.5	Bandpass filter sharpness

Usage

1. Open Audacity
2. Generate → Green Noise Gen (Golden ratio LFO v1.2)
3. Configure parameters to taste
4. Click Generate

Technical Notes

• Uses the golden ratio (φ = 1.618...) and its reciprocal (1/φ ≈ 0.618) to create mathematically harmonious modulation patterns
• The inverse golden ratio for AM creates slower, gentler swells
• The golden ratio for filter modulation creates faster, more energetic tonal shifts
• Ideal for meditation, focus, sleep, and ambient sound design