后勤交响乐中两大最主要的情绪是愤怒和绝望，但就算是跟第七交响乐一样激昂的第九交响乐也用D大调为主音的三和弦来作为结束。

The two most prominent emotions in the later symphonies are anger and despair, but even the Ninth, almost as bleak as the violent Seventh, ends on a root-position D major triad.

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实验结果表明，在钢琴的中低音区，不论是单键发音，还是三度和声、五度和声或三度和弦，令第七、第九次谐波的幅度衰减，均能使钢琴声音的音质有所改善。

The result shows that, in the bass and median tone of piano, the timbre will be improved if the 7th and 9th harmonics are attenuated for either single-key, third harmony, fifth harmony or triad chord.

youdao

实验结果表明，在钢琴的中低音区，不论是单键发音，还是三度和声、五度和声或三度和弦，令第七、第九次谐波的幅度衰减，均能使钢琴声音的音质有所改善。

The result shows that, in the bass and median tone of piano, the timbre will be improved if the 7th and 9th harmonics are attenuated for either single-key, third harmony, fifth harmony or triad chord.

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