According to this website,
Tinnitus (or ear ringing) is proven by scientists to be the result of an alerting loss of hearing ability. The reasons behind this might be varying from the normal process of growing old to an incident or a proximity to a loud noise. What happens in this case is that the brain tries to compensate for the lost sound frequencies and to create new noise. This is what our ears hear.
Basically, every time you’re experiencing ear ringing, that means your limbic system (the brain section that deals with emotions and behavior) could not stop your auditory system from registering a sound it shouldn’t have been catching.
Is it true that ringing ears after a concert is a sign of permanent hearing loss, of a particular sound frequency?