声筒（麦克风） are used to 捕捉 声 They 测 共鸣 in the air caused by 声波 波 and convert these into 电子 信号 These 电子 信号 are then passed on to be 储存 in the 过程 of 錄/录 or fed to 扬声器 which convert the 电子 信号 back into soundwave 共鸣

There are many different 种类 of 声筒（麦克风） which come in many 形状 and sizes and they often 用 slightly different 技术 Powered ‘condenser microphones’ and unpowered ‘dynamic microphones’ are the most common 种类 With condenser 声筒（麦克风） being the more 敏感 of the two

Special 工具 are also available to 录 声 that travel through liquids and through solids Hydrophones can 录 声 that travel through liquids and are used to 录 underwater 声 While contact 声筒（麦克风） are able to 测 声波 that 通过 through 固体 对象