Noise cancelling headphones

[jjjjjj]

My dear wife's getting on in age and suffers from annoying, ringing noises, when she wants to go to sleep.
I guess... the noise is a sinus wave and to combat it I imagine... a frequency and volume adjustible audio-sinewave oscillator could counter/cancel out this noise.
I suppose... works like an MP-Uzzi I used to practice with at the 'Bundeswehr' or like two same weight hammers bashed together... at the same speed.
Now it's over to you experts... neither relying on guesses, nor imagination or suppositions... because you have have got certainty on this matter and circuit for me. Thx in advance, it might safe us doctor's bills. Anxiously awaiting your reply!!! Kind Regards from old jjj in Chile

 

[Hero999]

It's called tinnitus and is generated internally so noise cancelling headphones won't help. I strongly advise her to go and see a doctor as it could be causd by numerous things.

I've suffered from mild tinnitus for a long time and fortunately it hasn't affected my hearing, at the age of 16 (when I first noticed it) I had my hearing tested and it was off the scale. I don't know when I first starting suffering from tinnitus I suppose it slowly crept up on me but it's not got much worst since then so I don't worry about it now. I've noticed that it seems to get worse when I bite really hard so I assume it's due to the jaw being connected to the nerves in my ears some how.

At the moment the only treatment I can suggest is white noise. There are circuits around on the Internet that you can build or you could just try a radio out of station. Good luck I hope it's nothing nasty.

 

[jjjjjj]

Thank you hero999...
White Noise, hey? Good to know. I told her to try her Sony Walkman's out of station noises... See how she goes with that.

 

[audioguru]

Asprin and acetylenol or whatever the pain relief drug is called cause tinnitus. There are newer pain relief medicines (Advil?) that do not cause tinnitus.
The doctor might know.

 

[RadioRon]

The idea of generating a tone to try and cancel out the internally heard sine wave is interesting in theory, but in practice the biggest problem with it is that you need to have a phase relationship between the two of about 180 degrees or it won't be of much help. While it would be possible to manually dial up the phase of the cancellation tone (externally generated) in a pair of headphones, the chances that the two tones will stay at 180 degrees out of phase without some sort of feedback control seems very low to me. The other problem is that it doesn't seem obvious to me that the internally heard tone is sinusoidal. If not, then you also face the problem of trying to cancel out the harmonics as well. This would require that you find a waveshape in your cancellation tone that happens to work, which would require some lucky guesswork I think.

 

[Sceadwian]

I don't suffer from it but I do notice a ringing sound when in a dead silent room, it has to be utterly dead silent though. I typically sleep with a fan on for background noise because I wake easily from small noises and that completely eliminates me hearing the ringing sound, but I'm sure my case is extremely mild. A fan or other white noise generator might help your wife, you'd never be able to exactly duplicate the sound she's hearing because it's not a sound that's being generated, it's a nerve problem. Even if you were able to exactly duplicate and invert the frequency that she appears to be hearing the nerve ghost noise would be over ridden by the real sound. In order to properly cancel it out you'd have to actually cancel out the nerve impulses that are causing it, and that's not physically possible.

 

[Hero999]

That's true, also in my experiance the frequency and amplitude are never constant so even if you were to tune a signal generator to the right frequency and phase it will soon drift out.