So I have just grazed this thread; in the past I have given this account elsewhere, but I would like to state a word of caution to anyone considering that which pertains to this thread:
I did something similar to what is being discussed here; I matched the frequency of my tinnitus to a raw audio file (G6, or 1567.98 Hz), and I looped the pitch in to my ears with headphones for about 20 to 40 minutes, utilizing the same medium volume that I used to listen to music at. I can say that my tinnitus did very much subside, but along with it came Hyperacusis, hearing loss, swelling/ear-fullness, and inner ear exhaustion. My conjecture is that I simply pinpointed my area of damage and attacked it with a precision sound blade. I have since internalized that it is a ridiculous notion to attempt to alleviate hair cell damage with more sound.
I'm not really trying to debate anyone, as I see has gone on here in the recent past; I just wanted to give my anecdotal account of a similar concept. Honestly, I would never even have found this forum if I hadn't made that mistake...
Edit:
I think I should add that early on in my hyperacusis onset, I tried Pink Noise therapy, and it was helpful, but I am not sure if it just killed off the higher frequencies that were damaged, and provided some relief, or if it was galvanizing healing by aggravating damage with "micro-injuries"; I had lots of fleeting tinnitus or "ear-resets" in that time frame, and I did stabilize for years. Perhaps I was just naturally healing as well, since I wasn't far from the onset. Hard to say, but there could be some application in noise therapy depending on your specific biology, but it is so difficult to quantify that. I would still strongly warn caution.