Audio Unit (AU) plug-ins that appear as Audio Modules within the Mac version of Isadora are 'pulled-in' from the available set provided by the MacOS. They include valuable tools such as AUSoundInput, AUGraphicEQ and AUAudioDeviceOutput.

Once these modules are patched with an audio stream, you can double-click the module to access a control pop-up interface. Be careful, though! Isadora does not develop these modules, and compatibility and interface issues require a modicum of know-how AND patience. 

There are also third-party Audio Unit plugins that can be installed.  A good starting place if you want to experiment with more AU audio effects is the FREE bundle available from: Melda

Here is a preview of their MNoiseGenerator being modulated by active inputs from an Isadora patch...