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BYU Professor Trying to Make Office a Quieter Place

This BYU professor noticed how noisy the fans for his computer were in his office, so he is working on noise-cancelling technology to make them silent. According to the article:

Their noise-control unit consists of four tiny loudspeakers and microphones built into the case around a fan.

The four microphones measure the fan's noises and signal a tiny microprocessor that drives the speakers, which make sound waves precisely canceling out the sound waves of the rotating fan blades. From the speakers come a sound pressure inverse to the pressure made by the fan, Sommerfeldt said.

Once it's perfected, the fan should be completely silent.

The thought of a completely silent microwave oven is intriguing.

Now we need the same thing for vacuum cleaners, circular saws and blenders...