And,the professor suspects that early humans liked ivory flutes more because the instruments produced a deeper,richer sound.

VOA: special.2009.08.18

So those are the three pieces and the issues there had to do with musical genre that we're going to talk a little bit more about in a moment, and the instruments.

就是这三首乐曲,与它们的音乐风格相关的知识,我们接下来会进一步探讨,还有关于乐器的知识

耶鲁公开课 - 聆听音乐课程节选

In his research paper, Hubble said the issue could be decided only by more powerful instruments.

VOA: special.2009.04.29

The telescope recently received new equipment and instruments to make it even more powerful.

VOA: special.2009.09.30

Then he added more musicians and instruments from other countries.

VOA: special.2009.07.31