Not sure about that stuff about tinnitus being a frequency dying. The sound of tinnitus is fairly broad-band, not just a single frequency (most people would describe it as a pitchless, high-frequency ringing). It would represent a fair sized chunk of the audible spectrum.
From what I remember, the part of the ear that we hear with (the basilar membrane) is covered in tiny auditory receptors that have a hair-like trigger. As sound waves propagate through the cochlea it triggers the receptors, and we get information about frequency from both the timing between successive triggers, and the position of the triggered receptor along the basilar membrane (the membrane is fatter at one end, so its resonant frequency changes along its length).
The type of tinnitus that’s related to hearing damage is caused by these receptor cells going into self-oscillation (triggering themselves off for no good reason), giving the illusion of sound.
