Facebook wants users to know exactly when they receive a private message, someone writes on their Timeline, etc. For that reason the social network  is testing new sound notifications.

The new alert sends out a ping sound when someone interacts with your Facebook account, much like the noise your phone sends when a text message is received.

A representative for Facebook tells Mashable:

“We are currently testing a sound with notifications. It’s only testing with a small percentage of people and it can be controlled from the Account Settings page.” read more