震音（tremolo），一般为拨弦乐器和弓弦乐器的演奏技法。

震音于拨弦乐器不同于「轮指」，是以3根或以上手指依次快速均匀地弹拨同一根弦。琵琶的轮指一般为5指轮指，另有结合其他技巧的轮指，如「带轮」、「扫轮」等。结他的轮指通常以无名指、中指和食指参与轮指，拇指弹奏低音旋律或和音。

弓弦乐器的震音则是弓在同一根弦快速来回运弓。

In music, tremolo (Italian pronunciation: [ˈtrɛːmolo]), or tremolando ([tremoˈlando]), is a trembling effect. There are two types of tremolo.

The first is a rapid reiteration

A second type of tremolo is a variation in amplitude

Some electric guitars use a (somewhat misnamed) device called a "tremolo arm" or "whammy bar" that allows a performer to lower or raise the pitch of a note or chord, which is known as vibrato. This non-standard use of the term "tremolo" refers to pitch rather than amplitude. True tremelo for an electric guitar,electronic organ, or any electronic signal would normally be produced by a simple Amplitude modulation electronic circuit.