Sound headphone also requires a quality amplifier just like a top - grade loudspeaker.

靓声的耳机就如同高级的喇叭，同样需要高素质的放大器来伺候。

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Develop, Produce and Sales for Professional Audio Equipment. Including: Loudspeaker, Power Amplifier, Mixing Console and Audio Accessories.

研制，生产及销售专业音响器材。包括：专业音箱，功放，调音台及周边器材。

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At last, we design an experimental system including signal source, power amplifier array and loudspeaker array. Some experiments of the directive property of loudspeaker array are completed.

最后，构建了一实验系统，该系统由信号源、功放阵列和扬声器阵列组成，并在实验室环境下完成了线阵列扬声器组的指向性实验和测试。

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Another less-than-obvious hardware change is the addition of a feedback amplifier -- possibly something like this chip from NXP -- to the phone's loudspeaker.

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