一个声音合成器（通常简称为“ 合成 ”或“ 合成器 ”，也被拼写的“ 合成 ”）是一种电子乐器，其产生转换为声音通过电信号仪表放大器和扬声器或耳机。合成器既可以模仿仍然存在的声音（乐器，如钢琴，电子琴，长笛，人声，自然的声音如海浪等），或生成新的电辅音色之前不存在。它们通常起到与音乐键盘，但它们可以被控制经由多种其它输入设备，包括音乐序器，仪表控制器，指板，吉他合成器，风控制器，和电子鼓。无内置控制器合成通常被称为声音模块，并通过被控制MIDI或CV /门使用控制器设备，常常一个MIDI键盘或其他控制器。

A sound synthesizer (usually abbreviated as "synthesizer" or "synth", also spelled "synthesiser") is an electronic musical instrument that generates electric signals that are converted to sound through instrument amplifiers and loudspeakers or headphones. Synthesizers may either imitate the already existing sounds (instruments like piano, Hammond organ, flute, vocals, natural sounds like ocean waves, etc.), or generate new electronic timbres which were not existing before. They are often played with a musical keyboard, but they can be controlled via a variety of other input devices, including music sequencers, instrument controllers, fingerboards, guitar synthesizers, wind controllers, and electronic drums. Synthesizers without built-in controllers are often called sound modules, and are controlled via MIDI or CV/Gate using a controller device, often a MIDI keyboard or other controller.