Human brains tuned in most to vocal sounds.

人类大脑对大部分声音都能接收到。

Notice how the vocals sound identical to the original, even when the instrumentals switch up and get even faster.

请注意，人声听起来与原声完全相同，即便是在乐声发生转变甚至变得更急促的情况下依然如此。

The recordings show many kinds of vocal sounds that changed often.

录音显示了多种经常变化的声音。

Some languages even make vocal sounds using the epiglottis, like in some African languages.

有些语言甚至使用会厌发出声音，比如某些非洲语言。

Music is defined as " the art or science of combining vocal or instrumental sounds (or both) to produce beauty of form, harmony, and expression of emotion."

音乐被定义为声乐或乐器（或两者结合）艺术，且能够产生形态美和谐美，更能抒发情感。”

Narrator: To get the crowds really going and allow viewers in movie theaters to feel like they were part of that crowd they of course had to make sure the vocals sounded perfect.

旁白：为了让人群真正动起来，让电影院里的观众觉得他们是人群中的一员，他们当然必须确保人声听起来完美。