To reduce the entrance of noise in building, can we apply principal of defective interferance or any other?

Answer 1

I think you mean destructive interference. This would mean measuring the sound at some point on the exterior of the building and generating a sound with exactly the same waveform but the opposite polarity, so the two would precisely cancel.

First, you would need to do this at several points, because the sound coming from the road on the east is not the same as that coming from the playground on the south. Second, the cancellation would not be perfect, so you would still hear some noise. Third, this system requires initial cost and continuous power.

In modern buildings, people like to shut off the outside with its noise, odors, pollen, dust, temperature variations, and fresh air. They prefer to solve these problems with insulation for both heat and sound. But if you prefer fresh air, an active noise cancellation system like this might be appropriate at each open window.

Noise cancellation is currently done for some microphones and for some headphones. It's more cost-effective because it's more local and its value is higher.

Answer 2

hi friend .........
your Questions is created all people in India because in India very noise pollution . so solve this question is as fallows .
1> all intrans door n widows make soundproof .
2> make sound absorption materials on outer wall of Ur building
3> plaster of Ur outer wall must be with thick sand due to this sand sound may be absorb .
4> and decorate Ur internal home wall with painting . and speared carpet on floor .
thees point are reduced noise in building