Sorry to bring up an old thread but I thought this subject was quite interesting (and I'm near my third week of recovering from knee-replacement surgery so I'm getting kind of bored).
I have a mild case of tinnitus and like a previous poster has stated is like standing in a field or forest on a summer night with all the bugs singing. I do occasionally experience ringing but it usually last a couple of seconds at most and then just goes away.
Not to get OT but the reason I bring this up is it seems that cycling clubs now seem to insist on inviting live bands to their invitational ride events. This is a big no-no for me since the bass and reverb of the loudspeakers can by pure torture for my hearing. The last invitational ride I participated in I went to get my after-ride meal and I had to scream over the noise of the admittedly-crappy band to tell them what kind of food I wanted. I ended up taking my food with me out to the car and left the venue. Not enjoyable at all.