Noise is a general term for unpleasant sounds. It will not only affect our lives but even do harm to our bodies. In order to prevent noise, there have been experiments on parametric and directional speaker systems since the early 1960s. So, what is a directional speaker?What is Directional Speaker?T

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We have already done some simple analyses on the piezo buzzer, magnetic buzzer, and mechanical buzzer before. In fact, some basic knowledge about them has already been understood. It is essential for us to be damaged during use. If there is no suitable replacement and it is urgent, then could we rep