Plugin Guide
How to Use Choroboros
Five engines, ten algorithms, a built-in Dev Panel, and presets. This guide covers everything — from loading the plugin to using the interactive console.
Quick Start
Load Choroboros on a track in your DAW. You will see the main panel with four knobs (Rate, Depth, Offset, Width), a Color slider at the bottom, and a Mix knob on the right. The top bar has the Kaizen DSP logo, a preset browser, and an engine selector dropdown.
The workflow in three steps:
- Pick an engine and mode. Use the engine dropdown (top right of the header bar) to select Green, Blue, Red, Purple, or Black. Toggle HQ on or off — each engine has two distinct algorithms.
- Shape your sound. Set Rate and Depth for movement, Offset and Width for stereo, Color for the engine's character, and Mix for dry/wet balance.
- Save it. Use the preset browser in the top bar to save your settings as a user preset. Click the + button, name it, done.
The Controls
Eight parameters are exposed to your DAW for automation. Six are visible as knobs/sliders on the front panel.
Rate 0.01 – 20 Hz
LFO speed — how fast the chorus modulates. Low values (0.1–0.5 Hz) give slow, sweeping movement. Higher values (2–20 Hz) create vibrato-like effects. Right-click Rate to open the tempo sync overlay with straight, triplet, and dotted note divisions that lock to your DAW's BPM.
Depth 0 – 100%
How far the delay time swings. Low depth gives subtle shimmer. High depth creates pronounced pitch wobble. Each engine maps depth differently — Red BBD uses it to control the clock sweep range, while Purple uses it to scale the warp polynomial.
Offset 0 – 180°
Phase offset between the left and right LFOs. At 0° both channels move together (mono-compatible). At 90° you get classic stereo chorus decorrelation. At 180° the channels move in opposite directions for maximum width.
Width 0 – 200%
Stereo spread using mid-side processing. 100% is natural stereo. Below 100% narrows toward mono. Above 100% exaggerates the stereo image — useful for pads, but check in mono to avoid phase cancellation.
Color 0 – 100%
The character knob — what it does depends entirely on which engine is active:
- Green: Bloom — adds thickness and gentle high-frequency damping. No saturation.
- Blue: Focus — tightens the high-pass, adds a presence peak. Clean clarity.
- Red NQ: Saturation — drives the BBD wet path harder.
- Red HQ: Tape tone and drive — controls the tape saturation curve.
- Purple NQ: Warp intensity — increases the phase-warp polynomial amplitude.
- Purple HQ: Orbit blend — mixes between the two rotating delay taps.
- Black: Mod intensity / ensemble spread — controls decorrelation between voices.
Mix 0 – 100%
Dry/wet blend. 0% is fully dry, 100% is fully wet. Start around 40–60% for mixing chorus, or push to 100% on a send channel.
Tip: Double-click any value label to type an exact number. Double-click a knob to reset it to default.
The Five Engines
Green — Classic (Bloom)
Best for: Gentle width, transparent mixing, acoustic instruments, vocals that need subtle movement.
The reference chorus. Normal mode uses 3rd-order Lagrange interpolation for a smooth, familiar character. HQ mode uses a 6-point 5th-order Lagrange polynomial for richer harmonics. The Color knob controls bloom — thickness and high-frequency damping without adding any saturation. Start with Rate around 0.5 Hz, Depth at 20%, and Color at 15% for a classic, understated chorus.
Blue — Modern (Focus)
Best for: Modern pop vocals, surgical stereo width, transparent production.
Clean and phase-accurate. Normal mode uses Catmull-Rom cubic interpolation. HQ mode uses a 5th-order Thiran allpass filter — maximally flat group delay, meaning it preserves transients and phase relationships better than any other engine. The Color knob controls focus — a combination of high-pass shaping and a presence peak around 2–3.6 kHz. For vocals, try HQ mode with low Depth (10–20%), moderate Width (100–150%), and Color around 40% for articulate stereo presence.
Red — Vintage (Saturation / Tape)
Best for: Electric guitars, retro synths, lo-fi character, anything that wants analog warmth.
Two very different algorithms live here. Normal mode (BBD) emulates a bucket-brigade device — a sample-and-hold delay with first-order hold output and a 5th-order Butterworth lowpass that tracks the clock frequency. The Color knob adds saturation to the wet path. HQ mode (Tape) is a varispeed tape emulation with Hermite interpolation, wow (slow drift around 0.33 Hz) and flutter (fast jitter around 5.8 Hz), and tanh saturation. The Color knob controls tape tone and drive. For vintage guitar chorus, try BBD mode with Rate 0.6 Hz, Depth 20%, Color 50%.
Purple — Experimental (Warp / Orbit)
Best for: Sound design, evolving textures, ambient production, anything that wants to sound unusual.
Normal mode (Phase-Warped) applies a nonlinear function to the LFO phase, creating modulation that speeds up and slows down within each cycle. The result is shifting, evolving textures rather than uniform movement. HQ mode (Orbit) uses 2D elliptical modulation with a rotating projection axis and dual delay taps — the modulation moves in a plane rather than along a line. The Color knob controls warp intensity (NQ) or the blend between the two orbit taps (HQ). For ambient pads, try Orbit mode with Rate 0.12 Hz, Depth 50%, Width 200%, Color 13%.
Black — Linear (Core / Ensemble)
Best for: Bass, dense arrangements where CPU matters, transparent multi-track chorus, and as a neutral reference.
The most CPU-efficient engine. Normal mode is straightforward linear interpolation with smooth delay tracking. HQ mode adds a second delay line with independent depth, offset, and blend — a dual-voice ensemble. The Color knob simultaneously controls the second tap's mix level, depth scale, and delay offset for progressive decorrelation. No saturation, no filtering — just clean modulation. Use it when you need chorus on 20 tracks without taxing your CPU.
Presets
The top header bar includes a preset browser — use the left/right arrows to cycle through presets, or click the preset name to open a dropdown. The + button saves your current state as a user preset.
Factory Presets
| Preset | Engine | Mode | Character |
|---|---|---|---|
| Classic | Green | NQ | Gentle bloom, 0.65 Hz, light movement |
| Vintage | Red | HQ (Tape) | Warm tape character, 50% color |
| Modern | Blue | HQ (Thiran) | Clean focus, 53% depth, wider stereo |
| Psychedelic | Purple | NQ (Phase Warp) | Slow, evolving warp — 200% width, 69% wet |
| Core | Black | HQ (Ensemble) | Neutral ensemble spread, 159% width |
| Duck | Purple | HQ (Orbit) | Fast 10 Hz orbit, 100% wet — vibrato territory |
| Ouroboros | Blue | HQ (Thiran) | 2 Hz, 65% color, 100% wet — dense focus |
Each engine also remembers your last settings independently. When you switch from Blue to Red and back, your Blue settings are restored automatically.
The Dev Panel
Click the DEV button in the animated drawer at the top right of the plugin to open the Dev Panel. It opens as a separate resizable window. This is where Choroboros goes beyond any other chorus plugin.
Seven Tabs
Overview
Signal flow visualization and live parameter readouts. Shows both raw (normalized 0–1) and mapped (display-unit) values for every parameter, plus a delay visual subtab for verifying smooth delay movement. Start here to confirm your target engine, core, and HQ mode before tuning anything.
Modulation
Live LFO scopes for left and right channels, a delay trajectory visualizer, and an LFO control workbench with sliders for Rate, Depth, Offset, and Width. Watch the LFO shapes and trajectory in real time as you adjust parameters. This is the fastest way to understand how Offset and Width interact to create stereo movement.
Tone
Two subtabs. Spectrum shows a real-time FFT analyzer with HP/LP filter overlays. Engine Response shows the transfer curve specific to each engine/mode combination — for example, Green shows the bloom response curve, Red NQ shows the saturation transfer function, and Red HQ shows the tape drive curve. Each engine response panel includes interactive tone controls.
Engine
Three subtabs. Signal Flow shows the runtime algorithm path. Engine Identity lets you inspect and change core assignments — which algorithm runs in each engine slot. With modular cores enabled, you can assign any of the 10 core algorithms to any engine/mode slot (e.g., put the Tape algorithm in the Green HQ slot). The third subtab is engine-specific macro controls (Bloom Macros, Tape Macros, Orbit Macros, etc.).
Look & Feel
Five subtabs for parameter mapping curves, UI interaction feel, per-engine layout positioning, global layout values, and text animation settings. This is where you fine-tune the front panel's visual behavior.
Validation
Three subtabs. Telemetry shows real-time CPU timing, input/output peak levels, callback counts, and engine switch counters. Trace Matrix shows the full value flow from raw → mapped → snapshot → effective for every parameter. Console is the interactive command interface (see below).
Settings
Tutorial launcher, UI text size and color modes, theme presets (Engine Adaptive, Classic Hacker, Neutral Studio, High Contrast), accessibility options (color-vision assist for deuteranopia/protanopia/tritanopia, reduced motion, large hit targets, strong focus ring), console preferences, and persistence controls (Reset to Factory, Set Current as Defaults, Copy JSON).
The Interactive Console
The console lives in the Validation tab and gives you direct command-line access to the DSP engine. Type help to see all available commands. Here are the most useful ones:
| Command | What it does |
|---|---|
engine purple | Switch to Purple engine |
hq on | Enable HQ mode |
set rate 0.75 | Set Rate to 0.75 Hz |
get depth | Show current and previous depth value |
sweep color 0 1 3000 | Animate Color from 0% to 100% over 3 seconds |
watch rate | Monitor Rate in real-time in the HUD |
search bloom | Find all parameters containing "bloom" |
diff factory | Compare current state against factory defaults |
undo / redo | Step backward/forward through parameter changes |
slot show | Show which algorithm is assigned to each engine/mode slot |
slot set red hq tape | Assign the Tape algorithm to Red HQ slot |
dump green | Print all Green engine parameter values |
export script | Copy all current settings as a script to clipboard |
tutorial bbd | Launch the BBD engine tutorial |
stats | Show runtime statistics |
Additional commands: add, sub, toggle, lock, unlock, bypass, solo, unsolo, macro, view, list, alias, cp json, save defaults, reset factory, import script, fx 0|1|2, core list, core show, history, clear.
12 Interactive Tutorials
Launch from Settings → Tutorial, or type tutorial in the console. Each tutorial is a guided walkthrough that automatically navigates you to the relevant tabs and highlights what to look at.
tutorial coreFull 34-step walkthrough of the entire Dev Panel
tutorial overviewOverview tab basics, raw vs mapped values
tutorial modulationLFO concepts, stereo motion, trajectory
tutorial toneSpectral analysis, engine response curves
tutorial engineSignal flow, core routing, macros
tutorial validationTelemetry, trace matrix, console
tutorial bbdRed NQ BBD emulation deep dive
tutorial tapeRed HQ tape chorus deep dive
tutorial phaseStereo phase relationships and offset
tutorial bimodulationPurple NQ phase-warp compound motion
tutorial saturationRed NQ saturation curves and drive
tutorial envelopeGreen HQ dynamic bloom controls
Where to Put Chorus in the Signal Chain
The standard approach for ambient processing. The chorus widens the source before it enters the reverb, creating a lush, diffuse tail.
Modulates the reverb tail itself. Produces a more defined, intense processed sound — reminiscent of 80s production techniques.
Choroboros has an internal Mix control, so it works as an insert with dry/wet blend. On a send, set Mix to 100% and control the amount from your DAW's send level. Using a send lets you EQ or compress the chorus independently — useful for keeping dense mixes clean.
The Top Bar
The header bar at the top of the plugin window provides quick access to everything:
Preset Browser
Left/right arrows to cycle presets. Click the name for a dropdown. + to save, − to delete user presets.
Engine Selector
Dropdown to switch between Green, Blue, Red, Purple, and Black. Switching engines changes the entire UI theme and restores your last settings for that engine.
Animated Drawer
Click the arrow at the top right to expand. Reveals four buttons: DEV (opens the Dev Panel), About (version and company info), Help (documentation links), and Feedback (built-in dialog that pre-fills your email client with usage stats).
Full Documentation
For the complete technical reference — every console command, every Dev Panel subtab, file locations, and troubleshooting — see the full documentation.
For the DSP architecture deep dive, see the technical article. For the full vision and roadmap, see the whitepaper.