While ordinary audio amplifiers including Class A and B amps make use of the linear amplification operation of the transistors, the Class D amplifiers signals are based on switching operations. This can render a large output power from a low power wattage and is used exclusively in the high-efficiency, high-quality subwoofer channel. Its high efficiency results in lower heat generation than Class A/B amps so that a high output can be supplied stably for long hours.