If you want to record external sounds using your computer, you’re going to have to use a microphone. However, you don’t need a microphone to record the internal sound from your PC. To do this, open Control Panel and click Hardware and Sounds. Then, select Sound. In the dialog box that appears, navigate to the Recording tab. Find the Stereo Mix entry and right-click it. Then, select Enable. If there are any microphone devices on your computer, disable them. Select OK to close the window. Now, use the Voice Recorder Windows app to record internal audio from your PC.