Cave Chorus

A lush, tri-voice ensemble chorus plugin inspired by the Mutable Instruments Plaits ensemble algorithm, built with JUCE.

Free and open source - no license required.

Features

Ensemble Design

• Tri-Voice Architecture - Three chorus voices at 120-degree phase offsets for rich, animated sound
• Dual LFO System - Slow (0.75 Hz) and fast (6.57 Hz) LFOs combined for complex, organic modulation
• Cross-Channel Routing - Sophisticated stereo image with voices routed across channels
• Mutable Instruments Heritage - Based on the acclaimed Plaits ensemble chorus design

Core Controls

• Rate - LFO modulation rate (0.1–5.0 Hz)
• Depth - Modulation intensity for pitch variation
• Mix - Dry/wet blend balance
• Width - Stereo spread (0% mono to 100% full stereo)

Sound Shaping

• Delay - Base delay time (1–20 ms) for chorus character
• Tone - High-cut filter on wet signal for darker textures

Factory Presets (24)

Classic: Vintage Ensemble, Slow & Wide, Subtle Shimmer, Warm Chorus, Lush Strings, 80s Synth, Rotary Speaker, Dreamy Pads

Modern: Stereo Spread, Fast Vibrato, Mono Thickener, Crystal Clear, Tight Double, Wide & Clean, Subtle Movement, EDM Pluck

Creative: Deep & Slow, Watery, Seasick, Flanger-ish, Tape Wobble, Alien Voices, Underwater Dreams, Broken Machine

System Requirements

• macOS 10.15+ (Intel & Apple Silicon)
• Windows 10+
• Linux (Ubuntu 20.04+)

Formats

• AU (Audio Unit)
• VST3
• CLAP
• Standalone

Installation

Download the zip for your platform from the Releases page.

macOS: Extract the zip and copy the plugin files to /Library/Audio/Plug-Ins/VST3/ (or Components for AU).

Windows: Extract the zip and copy to C:\Program Files\Common Files\VST3\.

Linux: Extract the zip and copy to ~/.vst3/ or your preferred location.

Building from Source

Requires CMake 3.25+ and a C++23 compatible compiler.

# Configure
cmake -B build -G Ninja

# Build all formats
cmake --build build

# Run tests
ctest --test-dir build --output-on-failure

License

GPL-3.0. See LICENSE for details.