By enabling original sound, you are preserving the sound of your microphone by turning off any echo-cancellation or audio enhancement. When playing a musical instrument this will avoid any distortion of high and low frequencies.
Stereo audio involves two independent audio channels. If your technical setup encompasses this, stereo audio must be turned on in Zoom, otherwise all music examples will be in mono.
How to Enable Original Sound & Stereo Audio in Zoom
Zoom Web Portal
Sign in on your Zoom web portal. Click Settings. Select the Meeting tab at the top and scroll down to In Meeting (Advanced) settings. Turn On Allow Users to select original sound and Allow users to select stereo audio in their client.
Sign out and close the Zoom Desktop Client. Open the Zoom Desktop Client and sign back in. Click the Settings icon and choose the Audio tab. Check Enable Stereo. Click Advanced. Check the Show in-meeting option to enable original sound from microphone.
Zoom Mobile App
Sign out and close the Zoom App. Open the app and sign back in. Click Settings followed by Meetings.
Enable Original Sound During Zoom Session (for Desktop)
Click Turn on Original Sound in the top-left corner of your Zoom Meeting.
Additional Settings for Music Performance
Desktop Audio Settings: Uncheck automatically adjust microphone volume, set suppress background noise to low. Click Advanced. Put Echo Cancellation on Auto.
Under Original Sound: Check Disable Echo Cancellation (if using headphones), High Fidelity Music Mode, and Use Stereo Audio (if using stereo mics).