There are times when you do not want to hear music: When your watching a movie, studying for exams, etc. These are the times when your neighbor's daughter's boyfriend feels the urge to park his car in front of your dwelling and share his bad taste in music by jacking up the volume and vibrating your windows. BOOM BOOM-BOOM BOOM-BOOM (repeat).

A small device with a microphone in front is aimed at the offending noise. An onboard processor calculates the frequency and amplitude of the sound waves needed to cancel out the sound waves coming from the noise source. The canceling waves are emitted from a speaker in the rear of the device, which mix with the sound waves of the obnoxious noise as they pass. A harmonic is created which cancels out both sound waves producing nothing but delicious silence.
-- frakamazog, Jul 03 2003

Noise-canceling car stereo http://www.halfbake...ling_20car_20stereo
Which I mention only because I seem to have deleted my "Bass-Seeking Missile" idea. [phoenix, Oct 04 2004]

I can't really comment on the feasibility of such a device, but you get a croissant from me for the sentiment. This phenomenon (and also the related one of people putting their speakers on the window-sill of their flat, facing outwards) never ceases to amaze me - these people's intention is, i suspect, not to listen to the music at a very loud level, but just to exhibit how brilliant and cool their taste in music is, though the result is that everybody just thinks "what shit music you fucking cretin".
-- sild, Jul 03 2003


"BOOM-BOOM", said the double-barrled shotgun.
-- thumbwax, Jul 03 2003


It's kind of active noise reduction device, but your idea features selection of signals to be silenced down. I don't know if this would work...
-- kyokpae, Jul 03 2003


//it would emit sound that from many points//
What if you have an emitter/sensor array built into the road? It would send the pulse under the vehicle, close to the source. Of course that might cancel or greatly affect the sound INSIDE the car. If the occupants crank it up to compensate, you’ll still have rumbling earth, even if it cancels the noise.
-- Amos Kito, Jul 03 2003



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