Noise Cancelling application, Please Help!!

[TheBigDino]

Hello People!!

 

Please Help!!

I've just came up with an idea of making a noise cancelling application and I've no idea where to start.

Basically (Well, it probably quite hard to do), what I want to do is, retrieve input from the microphone IN and inverse the wave of the input (Mic) and play it back to the speaker so that it could cancel out the noise from the surroundings of my Headphones(Speakers).

 

Any Ideas?

Also, Could somebody tell me if this is right, if inversing the wave really does cancel out the noise?

[Sayonara]

Yes, it's possible; you can buy headphones that do that.

[TheBigDino]

Yea, I know, there are also circuits out there that does it as well. But to keep the cost down I just thought it would be a good idea if a COMPUTER did it.

[5614]

with headphones i think a critical thing to remember is the size of it.... you cant walk around with a computer balancing on your head.

 

as sayo said these already exist, what many commercial companies do is buy one of these, take it apart to understand it and then to a degree copy it, with what they class as improvements and modifications.

[Dave]

I'm pretty sure you can buy little IC chips that have a mono input for a mic amd output for a stereo. Haven't found any yet though.

[YT2095]

noise canceling Microphones are in use on most pilot headsets and some posh Ham Radio gear, it`s been out for some while now, and there is an analogue way to accomplish this effect, the use of companders is also popular, but mostly on stage mics.

[ed84c]

I was just about to post this thread myself actually.

 

They are in commercial use now for road works etc. Mabye doing a google for Road Works sound cancellation?.

 

Also is it possible to cancel the noise by just replaying the noise exactly one half wave later than the sound, or would this only work if it is menotonous?