Identifying alert sounds I've been hearing this unfamiliar "alert" sound – kind of like a badly played guitar string slapping against the frets. After the sound occurs I don't see any new badges or any other indications that something happened…

I've been though all of the stock sounds in System Preferences > Sounds > Sound Effects and while Basso sounds close (hard to say for sure since I can't make the sound happen on demand) I don't think it is the one. 

So the question, in three parts:


Is there any way to identify the source of alerts?
If I knew the name of the sound, would that help? (Should I / could I go looking for places where Basso is used?
Can "non-stock" sounds be used for alerts?


I'm running the 10.12.3 beta on a Mid-2014 MBP.
SE Chat plays a twanged rubber band sound when someone pings you with @yourName in a room you have open.

You can change that pref by clicking the speaker icon at the top of the chat room.