Overview

This module is used to 'host' any Audio Unit synthesizer or effect.

At startup time Numerology searches for all AudioUnits on your system, then creates prototype instances of them sorted into two categories: AudioUnit Synths, and AudioUnit effects.

You can add as many AU synths and effects as you want to a Numerology stack. When you add them, Numerology will make a 'best guess' effort to route them appropriately: The MIDI input for synthesizers is connected to the first preceding MIDI output, while the audio input for effects is connected to the first preceding audio output. In both cases, all audio outputs are connected to the next following audio input.

If you add an AU synth or effect to a stack, and the routing does not seem to be right, be sure to take a quick look at the Routing page to check the connections.

All AudioUnits support an editor window for tweaking their parameters. Use the Edit button to bring up the editor window for the plugin.

The Audio Unit plugins Volta, from MOTU, and Silent Way, from Expert Sleepers have extra feature support in the form of additional ports and audio connection options. For more information on support for these plugins, see the appendix.

AU Presets

The AudioUnit spec provides for a standard way for Audio Unit hosts to load and store the settings for AUs running in their projects. Numerology supports this feature via the "Load" and "Save" buttons on the AudioUnit module, which allow you to load and save AU settings to preset files on your computer. There are two standard locations for storing AU presets on your computer, one is in /Library/Audio/Presets on you hard drive, and the other is ~/Library/Audio/Presets where ~ refers to you home directory. Numerology always defaults to the second choice, under the assumption that you are more likely to back up your home directory rather than an anonymous root-level directory.

In addition to user presets, Audio Units may also support "factory" presets, which are pre-loaded into the plugin. If an AU has any factory presets, Numerology will display a "Factory" button that you can use to load them.

When you save a project, Numerology will also save the settings for all your AU modules. These 'internal' AU preset files are stored in a "Media" folder that is created alongside your project file. The media folder will have the same name as your Numerology project, but with a ".media" extension added to it. This makes it easy to move projects from one computer to another without having to keep track of which presets also should be copied.

AudioUnits and ParamMod

Numerology's ParamMod feature is the key to AudioUnit modulation nirvana. Even though most AU plugins have their own internal modulation schemes, using Numerology's sequencers, LFO's and envelopes to modulate parameters in an AU plugin makes for a much more organic sound that integrates directly into your composition. The easiest way to setup ParamMod on an AU parameter is via the "Add Modulation" menu item in the Stack menu. There's more information on how to use it here.

AudioUnits and ReWire

Due to issues with the way most AudioUnits are implemented, Numerology cannot host Audio Units when in ReWire mode. If you wish to sync Numerology to another program and still host AUs in Numerology, you should use MIDI Sync, as described in the App Integration and Synchronization chapters.

Parameters

This is controlled via the small 'power' button on the module header. It is present on every Numerology module, but is especially important for AudioUnits. Since audio synthesis and processing can be very CPU intensive, it can be very useful to turn things off when they are not needed. This is what bypass does: it skips evaluation of the AudioUnit. In the case of AU effects, audio passes through unchanged. And since the bypass setting can be on or off for any preset, you can use it to turn AU's on and off for each stack preset.

Ports

This allows you to send MIDI to your AU, very handy for triggering notes in AU synths.

This port appears on AU's that have an audio input.

This is the audio output port for the module.