àudio

Áudio refers to the representation, transmission and reproduction of sound. In technology, the term covers electronic signals that encode audible information for storage, processing and playback. An audio signal can originate from acoustic sources converted to electrical form by a microphone or be produced directly by digital synthesis.

A typical audio chain begins with a transducer such as a microphone, followed by preamplification, analog-to-digital conversion, digital processing or storage, and digital-to-analog conversion for playback through loudspeakers or headphones. Audio systems may process signals in real time or store them for later retrieval.

Audio can be analog or digital. Analog audio preserves a continuous waveform, while digital audio samples the waveform at discrete intervals. Key parameters include sampling rate and bit depth; higher values yield more accurate reproduction but require more data. Common sample rates are 44.1 kHz for music and 48 kHz for video; 16-bit depth is standard for compact discs, while 24-bit is common in professional contexts.

File formats vary by compression and quality. Uncompressed formats include PCM in WAV or AIFF; lossy compressed formats include MP3, AAC and Ogg Vorbis; lossless formats include FLAC and ALAC. In broadcasting and recording, professional interfaces and standards such as AES/EBU, S/PDIF and various analog formats are used.

Applications span music production, film and television sound, telecommunications, streaming media, gaming and assistive listening devices. The term also appears in several languages as a label for sound data or sound files, with orthographic variants such as áudio in Portuguese or Spanish.