Sound and Such

[TeslaUnit]

Hello, I am new to this forum and am not too experienced in physics. Thought I am currently taking Electronic Engineering courses, which is what bring me here. This is really more of a recommendation request than anything else.

 

Basically I have a project coming along where we hope to achieve some success in sound cancellation. The challenge has proven very difficult so far, especially in open 3rd environments.

 

I was hoping to possible get some ideas on books or any kind of resources that might be able to help me in this project. For instance I really need a good book recommendation on the physics of sound, and how it is distributed (Something light in terminology would be preferable).

 

Thank you for your replies.

[Klaynos]

There's an interesting article in this months Physics World if you can get a copy called Cloak of silence revealed which is about how some researchers are converting things which are invisible to EM radiation into working for sound waves...

[YT2095]

I used make a version WAY back in the days of CB Radio, built into the hand held Mic.

it would have 2 mics basically, one on the front where you talk and one on the Back.

the front one was a directional mic and had several sound baffle layers, the one on the back was uni directional.

this run through an comparator OP-Amp and the sound from the Back was and front was compared.

Anything from the Back Mic that matched the front was canceled, and the remainder is what was Transmited

[Externet]

If the audio signals from two microphones are fed to a differential amplifier, its output will be only the audio which is sensed in real time by one microphone more than by the other.

 

That way, equal sounds reaching simultaneously to both microphones will not be amplified by canceling each other due to phase inversion of one by the differential amplifier.

 

Success depends much of microphone placement and directional characteristics. In open environment, sounds sources headings play a role in the success of the cancellation.

A "voice canceling schematic diagram" or "vocal remover..." search could yield further details.

Miguel

[TeslaUnit]

Well thank you for your inputs, Ill be sure to look into all your recommendations.