preamplifier

pre.am.pli.fi.er

n.（名词）
An electronic circuit or device that detects and strengthens weak signals, as from a radio receiver, for subsequent, more powerful amplification stages.
前置放大器：电子线路或装置，用来探测并加强无线电接收机所发出的微弱信号，从而使其达到更加有力的增幅程度