Where is the default notification tone setting of oppo mobile phone?

ColorOS 3.0 and above: "Settings >; Sound and vibration >: notification ringtone ",you can choose to customize the ringtone or the system's own ringtone.

Tips:

ColorOS 1 1 and above, in order to avoid the long-term ringing of the notification bell, the user-defined notification bell file only plays for the first 5 seconds at the longest.