VB-Audio Virtual Cable - Connect Audio Applications together with a Virtual Audio Device
SoundDesk Virtual Devices by LoudLab - SoundDesk Virtual Devices - Software devices to route audio across macOS.
Synchronous Audio Router - Routes Windows application audio to and from your digital audio workstation software.
Virtual Audio Cable - Ever wanted to record your speaker output? (loopback) This is for you.
SoundTap - Download SoundTap Streaming Audio Recording Software Free to record live audio, streaming music, internet radio easily in perfect pure digital on PC and Mac.
iShowU Audio Capture - iShowU Audio Capture is an extension to OS X to record audio from your computer.