Audiosignal

An audiosignal is a signal that encodes information about sound and can be processed by electrical or electronic devices. It may be continuous in time in the analog form or discrete when represented digitally. Audiosignals are used to transmit, store, or reproduce audible content across music, speech, and ambient sound.

Analog audiosignals are continuous electrical waveforms that mirror acoustic pressure variations or speech signals. Digital audiosignals are created by sampling the analog waveform at a fixed rate and quantizing the samples into numeric values. The sampling rate and bit depth determine the potential frequency range and the precision of the representation.

Common elements of an audio signal path include a source (voice, instrument), transducers (microphone, line input, speakers), and processing stages (amplification, filtering, compression). In digital systems, signals undergo analog-to-digital conversion and digital processing (DSP) before being converted back via a DAC.

Quality and fidelity are described by metrics such as signal-to-noise ratio, total harmonic distortion, dynamic range, and bandwidth. Aliasing, quantization error, and clipping can degrade an audiosignal. Proper sampling, anti-alias filtering, and dynamic range management are important.

Audiosignals are stored and transmitted in many formats and protocols, including PCM-based WAV or AIFF, compressed formats such as MP3, AAC, or lossless codecs such as FLAC, and streaming protocols. They are used in music production, broadcasting, telecommunications, film and gaming audio, and consumer audio playback.