Rubigo Rotary — User Manual

1. Introduction

Rubigo Rotary is a rotary speaker cabinet as an audio effect: put it on an organ track (or anything else) and it plays the sound through a cabinet with a spinning treble horn and a spinning bass drum, picked up by microphones. It is the same rotary engine as the one in Rubigo RB3, as its own plugin, so it can follow any organ, electric piano or synth.

The two rotors turn at their own speeds. As they swing toward and away from the microphones they make the pitch shift (Doppler), the throb and the swirl of the sound; when you switch speed, each rotor speeds up or slows down at its own rate, which is where the classic spin-up and spin-down comes from.

Signal chain

1. Input — the level going into the amplifier (mono or stereo in)
2. Amplifier — the cabinet's tube amp, or one of three overdrives, set by Drive (can be switched off)
3. Rotary cabinet — horn and drum through the crossover, the cabinet's voicing, and the microphones (stereo out)
4. Mix — the cabinet against the dry signal
5. Master — the output level

2. Quick Start

1. Install Rubigo Rotary (see Installation) and insert it on an instrument track after the instrument, or on a bus.
2. Play. It starts on Slow, with the amp on at half Drive and the microphones in the Room setup.
3. Click Fast on the speed switch and listen to the rotors speed up; click Slow to hear them come down again. Brake stops them.
4. For a dirtier sound, raise Drive; for more or less of it overall, use Input on the Advanced page (see Levels).
5. To switch speed from a keyboard: the mod wheel (CC 1) moves the speed switch and a sustain pedal (CC 64) flips between Slow and Fast, out of the box (see MIDI Speed Control).

3. Installation

Linux

Windows

%COMMONPROGRAMFILES% is normally C:\Program Files\Common Files (the plugin is 64-bit only). Copying there needs administrator rights.

macOS

macOS quarantines downloaded plugins that aren't notarized by Apple, and DAWs won't load them. Allow the plugin once by pasting this into Terminal:

xattr -dr com.apple.quarantine ~/Library/Audio/Plug-Ins/VST3/Rubigo_Rotary.vst3 ~/Library/Audio/Plug-Ins/CLAP/Rubigo_Rotary.clap

On every system, rescan plugins in your DAW afterwards if it doesn't find the new plugin by itself.

The plugin's window needs a graphics driver with OpenGL 3.x. Without it (some virtual machines, remote desktops, headless audio servers) the plugin still loads and plays, without its window: use your host's generic parameter list instead.

4. Licensing & Activation

The first time you open the plugin, the LICENSE card asks you to activate it or start the trial:

• Start 30-Day Trial — one click, no account, fully working for 30 days.
• Activate — paste the license key you received after purchase into the box (use the Paste button: some hosts keep Ctrl+V / Cmd+V for themselves) and click Activate.
• Buy — opens the Rubigo Audio store in your browser.

During the trial, a tag at the top of the window shows the days left; click it to open the LICENSE card and activate. Once the plugin is licensed the tag goes away; the ? button's About card shows the license state. When the trial is over, the LICENSE card covers the window until you activate.

Your license is tied to the computer you activate it on. To move it to another machine, get in touch (see Support).

5. Interface Overview

The left side of the window shows the cabinet, drawn from its open back: the horn at the top and the drum below it turn as the engine's rotors do, so you can see the speed you hear.

The top bar, over the controls:

• License tag (trial or not activated only) — opens the LICENSE card.
• BASIC / ADVANCED — the two pages of controls. Basic has what you play with; Advanced has the settings you set once.
• ? — the About card: the version, the license (with Buy during the trial) and a link to this manual; Copy URL next to it copies the address, for systems where clicking a link doesn't open a browser.

Every control is a regular plugin parameter: your host can automate it, and it is saved with your project.

6. The Basic Page

Speed

The speed lever: Slow (chorale), Brake (rotors stopped) and Fast (tremolo). Click a position to move the lever there. The order of the positions follows the switch order in the MIDI block on the Advanced page: Slow - Brake - Fast (the default) or Brake - Slow - Fast (see MIDI).

Amplifier

Enabled switches the amplifier in or out. Off, the cabinet gets a clean signal at the same loudness, so switching it changes the tone, not the level. Drive sets how hard the amp is pushed: low is clean and round, high breaks up into overdrive. Which amp it is: the Type on the Advanced page.

Levels

Master is the output level (−24 to +24 dB). Mix blends the cabinet with the dry signal: 100% is all cabinet (the default), lower values keep some of the dry sound under it.

Microphones

The diagram shows the cabinet from above, the way you face it (the front at the bottom), with the horn, the drum and the microphones where they are; the readout above it shows the distance and angle. Setup picks a placement:

Distance (20–200 cm) and Angle (0–180°, the angle between the two mics) move with the setup: picking a setup puts them at its values, and moving either one away from them switches the setup to Custom. Closer in gives more movement (throb and pitch shift); farther out gives a broader, more blended sound. The microphones can't be dragged inside the cabinet: Distance stops at its edge for the angle you set. Every setup is level-matched, so switching setups changes the picture, not the loudness.

Horn and Drum

Each rotor has its own Slow and Fast speeds (in turns per second, Hz) and its Ramp: the time it takes to get from one speed to the other. The horn is light and gets there in about a second; the heavy drum takes several, which is why, after a switch, the treble arrives first and the bass catches up. Slowing down takes a little longer than speeding up.

7. The Advanced Page

Amplifier

Type picks what drives the cabinet: 122 Tube Amp (the cabinet's own tube amp: warm, round, vintage overdrive; the default), Transparent OD (an overdrive pedal that keeps the tone), Op-Amp Dist (a harder distortion pedal) or Hot-Rod Crunch (a cranked lead amp). Input (−24 to +24 dB) is the level into the amp: see Levels.

Horn

• Radius (5–30 cm) — the horn's effective size: a bigger horn swings its mouth faster, for more pitch shift.
• Brightness (±6 dB) — tilts the horn's treble (a shelf around 3 kHz); 0 dB is the cabinet as modeled.
• Beam Focus (0.1–2.0) — how narrow the horn's beam is: higher is more directional, for a deeper throb as it passes the mics.

Cabinet

• Type — 122 / 147 (the classic two-speed cabinet, the default), Studio 12 or G37, each with its own horn compartment, drum, crossover and tone.
• Turbulence (0–100%) — the small random unsteadiness of the air and the rotors, so the movement isn't perfectly regular. Off (0%) by default.
• Horn/Drum Balance — more horn (treble) or more drum (bass); the middle is the cabinet as it is.

The MIDI block, on the right of the Advanced page, is described in the next section.

8. MIDI Speed Control

Route MIDI to the plugin (in most DAWs: a MIDI send or a sidechain MIDI input to the effect) to switch speed from your keyboard. MIDI enabled turns this on or off; Channel takes the controllers from one channel (1–16) or all of them (Omni, the default).

There are three speed functions, each listening to one controller (CC):

Each function shows its CC and a light that blinks when it receives it. To change one, click LEARN and move the control on your keyboard: the function takes the next CC that arrives, on any channel (if another function had that CC, it moves here). CLEAR removes a function's CC. The learned CCs are saved with your project. The line at the bottom shows the last CC received, its value and channel — even while MIDI is off — so you can see what your controller sends.

A speed change from MIDI moves the Speed parameter itself, so the switch on screen and your host's automation follow it. To control the other parameters from MIDI, use your host's own MIDI learn or automation.

9. Levels & Gain Staging

The plugin is calibrated for an organ around −18 dBFS RMS. At the defaults (Input 0 dB, Drive 50%, Master 0 dB) such a signal comes out at about the same level, so bypassing the plugin doesn't jump in loudness.

• Input sets how hard your signal hits the amp. A quieter source than that wants more Input; a hot one less. Input changes the amount of breakup at a given Drive.
• Drive is the amp's own drive: it changes the tone, and the amp keeps its loudness roughly even across the range.
• Master sets the final level without changing the sound.

10. Troubleshooting

The speed doesn't change from my keyboard

• Check that MIDI reaches the plugin: the bottom line of the MIDI block should show the CCs as you move the control. If it stays empty, route MIDI to the effect in your DAW.
• Check MIDI enabled is on and Channel is Omni or the channel your keyboard sends on.
• Check the function's CC matches what the bottom line shows; or click LEARN and move the control.

Clicking a link doesn't open the browser

Some systems have no working default browser for programs started by the DAW. Use Copy URL in the About card (the ? button) and paste the address into your browser.

The plugin doesn't appear in my DAW

• Check the install path for your system and format (see Installation).
• Rescan plugins: most DAWs keep a list and don't pick up new files by themselves.

The plugin plays but shows no window

The window needs OpenGL 3.x (see Installation). Without it the plugin runs without its window; audio is not affected. On Linux, glxinfo -B shows what your system provides.

11. Parameter Reference

12. Support

Questions, license transfers, or anything account-related — email support@rubigo.audio. For general chat and community help, join the Discord server.

Trademarks

Leslie is a trademark of Hammond Suzuki Co., Ltd. Rubigo Audio is not affiliated with, sponsored by, or endorsed by Hammond Suzuki. Cabinet model numbers are used only to identify the cabinet types the plugin models.

VST is a registered trademark of Steinberg Media Technologies GmbH. CLAP is an open standard by Bitwig and u-he.

Third-Party Software

Rubigo Rotary is built with these open-source components, used under their licenses:

The MIT and ISC licenses permit use, copying, modification and distribution, provided the copyright notice and the license text are included:

Permission is hereby granted, free of charge, to any person obtaining a copy of this software
and associated documentation files (the "Software"), to deal in the Software without
restriction, including without limitation the rights to use, copy, modify, merge, publish,
distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the
Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or
substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING
BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

(The ISC license of nih-plug grants the same permissions in shorter words, with the same condition and disclaimer.)

© 2026 Rubigo Audio. All rights reserved.