A stereo receiver is an electronic device that receives and amplifies audio signals from sources such as radio tuners, CD players, and turntables, and outputs them to speakers. There are several synonyms to refer to this piece of equipment, including AV receiver, amplifier, stereo system, stereo amplifier, and Hi-Fi system. AV receivers, which stand for audio/video receivers, are typically used in home theater setups, whereas stereo amplifiers are usually intended for two-channel audio systems. A Hi-Fi system is a high-fidelity audio system that delivers superior sound quality, often achieved through the use of high-end components and precise tuning. Regardless of the term used, these devices remain an essential part of any home audio setup.