When UAD software is installed, UAD plug-ins are copied to the following default locations:

Windows

VST (64bit)
C:\Program Files\Steinberg\VstPlugins\Powered Plugins\

VST (32bit)
C:\Program Files (x86)\Steinberg\VstPlugins\Powered Plugins\

AAX64
C:\Program Files\Common Files\Avid\Audio\Plug-Ins\

Mac

VST
/Library/Audio/Plug-Ins/VST/Powered Plug-Ins

Audio Units
/Library/Audio/Plug-Ins/Components

RTAS
/Library/Application Support/Digidesign/Plug-Ins

AAX64
/Library/Application Support/Avid/Audio/Plug-Ins