Virtual Audio Cable -

Virtual Audio Cable (VAC) is a software-based driver that functions as a digital loopback, allowing you to route audio streams from one application to another without physical hardware. It essentially acts as a "invisible pipe" where the playback side of one program (the "data sink") connects directly to the recording side of another (the "data source"). Virtual Audio Cable How Virtual Audio Cables Work

The cable is invisible, but the power is very real. virtual audio cable