A scientific analysis of ordinary everyday sounds has demonstrated some that are surprisingly similar to the experimental sounds which create temporary tinnitus. Prior personal experience had already shown the connection between such exposure and temporary ringing. These sounds are illustrated in spectral diagrams. Your hearing is overworked, even when you sleep. This supports the idea that that filtering or noise cancellation is the normal full-time activity.
Protection is provided by the middle ear muscles.
The inner ear is so exquisitely sensitive that the middle ear has evolved protection mechanisms. Support for the middle ear bones apparently includes three muscles which can be tensed under extreme conditions, to stiffen or fine-tune them. The middle ear has a gap, and a resonance, in sound transmission. We are not conscious of this defect because the middle ear protection system conceals it in the normal ear. Your parallel-lane information superhighway.