多媒体作为一种先进的教学辅助手段，已迅速得到普及，对作为其重要设备之一的功率放大器性能也提出了更严格的要求，它不同于民用设备，应具备以下特点：⑴整个电路要尽可能模块化，便于维修和更换。⑵有较好的音质、较大的功率储备和动态，使教室各个角落有足够的声压。⑶高 As a kind of advanced teaching aids, multimedia has been popularized rapidly. It also poses more stringent requirements on the performance of the power amplifier, which is one of the important equipments. It differs from the civilian equipment in that it has the following characteristics: (1) May be modular, easy to service and replace. ⑵ better sound quality, large power reserve and dynamic, so that every corner of the classroom have enough sound pressure. ⑶ high