Support for the terminal bell was introduced with JuiceSSH v1.4.5.
To configure the terminal bell in JuiceSSH there is an option in the Settings menu under the Terminal heading:
There are three options:
1. Disabled (default)
JuiceSSH will not react when a terminal bell is received
JuiceSSH will vibrate the device for 100ms regardless of whether the session is in the foreground or background.
3. Show Notification
If the session is in the background, JuiceSSH will update the session notification with the number of bells that have been received since the session was last in the foreground. It will also follow the device settings for the notification vibrate, notification ringtone, and device led settings.