放大器, 擴音器
an electronic device for increasing the amplitude of electrical signals, used in sound reproduction.
:
• He connected his guitar to the amplifier to make it louder.
他把吉他連接到放大器上，讓聲音更大。
• The concert hall had powerful amplifiers for the sound system.
音樂廳有強大的音響系統放大器。
