TEAC Replacement Stylus for PA688 Turntable Compression Circuitry limits distortion at earth-shaking volume levels. Built-in High Current Amplifier supplies all the good, clean power you need for big bass. LINE and SPEAKER level inputs ensure easy hook-up compatibility with virtually any system Signal-sensing smart amp Auto ON/OFF Circuitry knows when to turn itself on and off Non-resonant MDF construction with internal bracing for deep bass impact with superior detail, accuracy and musicality