An audiophile (from Latin: audīre, lit. 'to hear' + Greek: φίλος, romanized: philos, lit. 'loving') is a person who is enthusiastic about high-fidelity sound reproduction. An audiophile seeks to achieve high sound quality in the audio reproduction of recorded music, typically in a quiet listening space in a room with good acoustics.

Audiophile values may be applied at all stages of music reproduction—the initial audio recording, the production process, the storage of sound data, and the playback (usually in a home setting). In general, the values of an audiophile are seen to be antithetical to the growing popularity of more convenient but lower-quality music, especially lossy digital file types like MP3, lower-definition music streaming services, laptop or cell phone speakers, and low-cost headphones.

The term high-end audio refers to playback equipment used by audiophiles, which may be bought at specialist shops and websites. High-end components include turntables, digital-to-analog converters, equalization devices, preamplifiers and amplifiers (both solid-state and vacuum tube), loudspeakers (including horn, electrostatic and magnetostatic speakers), power conditioners, subwoofers, headphones, and acoustic room treatment in addition to room correction devices.

Although many audiophile techniques are based on objective criteria that can be verified using techniques like ABX testing, perceived sound quality is necessarily subjective, often with subtle differences, leading to some more controversial audiophile techniques being based on pseudoscientific principles.

An audio system typically consists of one or more source components, one or more amplification components, and (for stereo) two or more loudspeakers.

Signal cables (analog audio, speaker, digital audio etc.) are used to link these components. There are also a variety of accessories, including equipment racks, power conditioners, devices to reduce or control vibration, record cleaners, anti-static devices, phonograph needle cleaners, reverberation reducing devices such as speaker pads and stands, sound absorbent foam, and soundproofing.

The interaction between the loudspeakers and the room (room acoustics) plays an important part in sound quality. Sound vibrations are reflected from walls, floor and ceiling, and are affected by the room's contents. Room dimensions can create standing waves at particular (usually low) frequencies. There are devices and materials for room treatment that affect sound quality. Soft materials, such as draperies and carpets, can absorb higher frequencies, whereas hard walls and floors can cause excess reverberation.

Audiophiles play music from a variety of sources including phonograph records, reel to reel tape, compact discs (CDs), and digital audio files that are either uncompressed or are losslessly compressed, such as FLAC, DSD, Windows Media Audio 9 Lossless and Apple Lossless (ALAC), in contrast to lossy compression, such as in MP3 encoding. From the early 1990s, CDs were the most common source of high-quality music. Nevertheless, turntables, tonearms, and magnetic cartridges are still used, despite the difficulties of keeping records free from dust and the delicate set-up associated with turntables.