The sound reproduction amplifier has its frequency response selectable according to the type of sound carrier supplying the audio signals. The frequency response is altered by active or passive filters switched in and out by a selection switch. The frequency response may also be altered by networks designed to alter the pre-emphasis frequency and/or its magnitude or by limiters or resonant circuits. The selection switch is located on the amplifier's control panel but it may also be remotely controlled.
展开▼
