How to add the OS X system sounds to Big Sur. Make sure you save them before upgrading.

[MisterAndrew]

Big Sur replaces all the familiar system sounds with new versions. Here's how you can add the OS X ones we all love.

1. Save the Sounds folder located in System > Library in an OS X installation to a safe location.

2. Rename the sounds by adding Classic (or OS X, old, etc.) to the end of each file name. If you don't rename them then you can't select the new Big Sur sounds for alerts in other apps such as Mail because they will only show up as the new names, but the old sounds. This is because the new sounds in Big Sur still have the old file names, which are located in System > Library > Sounds.

3. In Big Sur copy your Sounds folder with OS X sounds to the Library folder (not System > Library, just Library).

Here are the name differences:
Basso > Mezzo
Blow > Breeze
Bottle > Pebble
Frog > Jump
Funk > Funky
Glass > Crystal
Hero > Heroine
Morse > Pong
Ping > Sonar
Pop > Bubble
Purr > Pluck
Sosumi > Sonumi
Submarine > Submerge
Tink > Boop

 

[MisterAndrew]

Okay, I think I have this correct now. I changed the instructions a couple times because at first I noticed the sound files have the same names in Big Sur, so I changed the file names for the old sounds. Then I noticed Big Sur changes the sound names from the file names in the Sound Preferences Pane for the sounds in System > Library > Sounds, but it leaves the names alone for sounds in Library > Sounds so I decided it was okay to not rename the old sounds. Then when I opened the preferences in the Mail app I discovered the system had renamed the old sounds and listed those only, so the old sound names do need to be renamed. Apple sure made this confusing.