Those are the only two tones.

只有这两个音调。

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Sometimes you hear two tones.

有时会听到2种音调。

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The harmonic combination of the two tones constituting the extremities of such an interval.

含有这样的五度音程的末端的两个音调的和声组合。

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If two tones, one high and one low, were played about 40 milliseconds apart, the best readers had no trouble telling which tone came first.

ECONOMIST: The cat sat on the tam | The

These showed that unless the two tones were sufficiently separated in time, only one electrical signal, rather than two, was generated by the brains of the affected mice in response.

ECONOMIST: Reading minds | The

He puzzled out (and only later learned that 19th-century German engineer Heinrich Helmholtz had gotten there before him) that when two tones are played simultaneously and loudly enough, they interact to spawn two new tones.

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