Edison's sound principle
Sound refers to other sounds besides human language and music, including the sounds of natural environment, animals, machines and tools, and the sounds made by human actions. Sound probably includes the peripheral equipment of power amplifier, including voltage limiter, effect equalizer, VCD, DVD and so on. , speakers, speakers, speakers, mixer, microphone display equipment, etc.
Among them, speakers are sound output devices, speakers and subwoofers. A sound box includes three kinds of high and low speakers, and three kinds are not necessarily three kinds. The development history of technology can be divided into four stages. We need to know the sound propagation mode of the speaker. The transmission of sound requires a medium vacuum, but not all gases, liquids and solids can transmit sound.