在我们日常生活中有两类声音,一类是乐音,听起来很舒服,增加美感,它包括了多种频率的声音,这种频率都有一定的周期性和节律性,所以很悦耳。另一类是噪音,听起来很难受,它是无一定规律的、偶然相结合的、混乱的杂音所组成的声音。生活中处处都可产生大量噪音,工厂中的机器轰鸣,各种工具叮叮当当的撞击声,马路上人群的喧闹,那些形形色色的汽车喇叭 There are two types of sounds in our daily life, one is musical sound, which sounds very comfortable and adds beauty. It includes a variety of frequency sounds, which have certain periodicity and rhythmicity, so it is very sweet. The other is noise, which sounds uncomfortable, it is a combination of random, chaotic murmur composed of no regularity. Everywhere in your life can produce a lot of noise, roaring machinery in the factory, a variety of tools rattled percussion, the crowds on the road, those all kinds of car speakers