VB-Audio Virtual Cable - Connect Audio Applications together with a Virtual Audio Device
TrueFire - The Best Guitar Lessons Online Fast. Easy. Fun.
SoundDesk Virtual Devices by LoudLab - SoundDesk Virtual Devices - Software devices to route audio across macOS.
AudioBus - With Audiobus, the revolutionary new inter-app audio routing system, you can connect your...
vsound - Vsound a virtual audio loopback cable - Vsound is an application which allows you to digitally record the output of another program such as RealPlayer.
Go Button - Go Button is a mobile audio app designed to provide professional playback of music and sound effects for live shows. It provides a creative, self-contained show control system that runs on your iPad, iPhone, or iPod touch.