Contour modulation is a technique in which a phase-modulated signal waveform and amplifier output impedance work together to maintain higher efficiency over a sizable output power back-off.

轮廓调制结合了一种相位调制信号的波形和放大器的输出阻抗，可在某个较大型输出电源关闭后保持更高的效率。

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The theory research results of one cycle controlled switching power amplifier show that the output signal follow the input signal linearly, and the control performance is decided by output filter.

理论分析结果表明，单周控制开关功率放大器的输出信号与输入信号成线性变化关系，其控制性能由输出滤波器决定。

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The term "efficiency" refers to the ability of a speaker system to convert electrical energy (power from the amplifier) into acoustic output.

术语“效率”是指扬声器系统将电能（功放的推力）转化为声音输出的能力。

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The Model Two makes use of the latest audio technology, including front and rear RCA pre-outs, subwoofer output and a built-in 25 watts x 4 channel RMS power amplifier.

ENGADGET: RetroSound's Bluetooth-enabled in-dash radio for classic cars now up for grabs