translation.en: But actually, the most fascinating thing that I found was that even the audio system or wave transmission nowadays are still based on the same principle of producing and projecting sound.
translation.zh: 实际上，我发现最美妙的事是 当时称之为的声音系统 现在叫做声波的传递 现在根本上还是基于同样的原则 来产生和放大声音。