It began with a study one of them did on a dolphin, who had been trained to recognize a particular high-pitched tone.

首先，他们中的一个人对海豚做了一项研究，训练它识别一种特殊的高音。

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The team then took a fundamental tone pitched below 5 kHz and digitally filtered it to leave just the overtones above 6 kHz.

研究小组接着选取一个音调低于5千赫兹的基本音，滤掉低于6千赫兹的所有声音。

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Be careful about the tone of your voice. Keep it evenly moderated and avoid getting a high-pitched, whiny or tearful tone.

对自己的语调要十分小心。使它保持均匀地…避免高嗓门、牢骚或哭腔。

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But when they downloaded the Larry The Bird character (which is also an app created by Outfit7), which has a high-pitched tone, they could understand what she was saying.

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While the message began its voyage to the cosmos--a 24, 000 year trip to M-13, a cluster of stars in the constellation Hercules, to be exact--visiting dignitaries listened over a loudspeaker while each bit played as a short, high-pitched tone.

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