Headphones using this characteristic use exterior microphones to seize the audio all-around you. They then reproduce matching frequencies with their period inverted to cancel ambient sounds. The battery is also extraordinary, with as much as 70 several hours of playback time (with no ANC) on one charge, and 50 hours https://hightech-headphones79012.blogpixi.com/34889415/not-known-factual-statements-about-hightech-headphones