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Aliasing (Audio)

Audio Aliasing

Distortion occurring when audio frequencies above the Nyquist limit are sampled, producing false lower frequencies.

Audio Codec

Software that encodes raw audio into a compressed format and decodes it back for playback (e.g. MP3, AAC, FLAC).

Audio Fingerprint

Acoustic Fingerprinting

A compact digital summary of an audio signal used to identify songs or detect duplicate content.

Bit Depth (Audio)

Audio Bit Depth

The number of bits in each audio sample, determining the dynamic range and noise floor (e.g. 16-bit, 24-bit).

Bitrate

Bitrate (Data Rate)

The number of bits processed or transmitted per second in an audio or video stream, directly affecting both file size and quality. Higher bitrates preserve more detail but produce larger files.

Channel

Channel (Audio Signal Path)

A single, independent stream of audio data within a recording. Mono audio has one channel, stereo has two (left and right), and surround sound configurations like 5.1 have six channels.

Chorus Effect

Audio Chorus Effect

An effect that duplicates a signal with slight pitch and timing variations to simulate multiple voices or instruments.

Clipping

Clipping (Audio Distortion)

A form of audio distortion that occurs when a signal exceeds the maximum level a system can handle, causing the waveform peaks to be cut off flat, producing harsh, unpleasant crackles or buzzing.

De-esser

Audio De-esser

A specialized compressor targeting sibilant frequencies (4-10 kHz) to reduce harsh 's' and 'sh' sounds in vocals.

Dithering (Audio)

Audio Dithering

Adding low-level random noise when reducing bit depth to mask quantization distortion and preserve detail.

Dynamic Range

Audio Dynamic Range

The difference between the quietest and loudest parts of an audio signal, measured in decibels.

FLAC

Free Lossless Audio Codec

An open-source audio codec that compresses audio without any loss in quality, reducing file sizes by 50-70%.

Loudness War

The trend of increasing audio loudness in mastering at the expense of dynamic range, countered by LUFS standards.

Pitch

Audio Pitch

The perceived frequency of a sound, determining how high or low a tone sounds to the listener.

Sample Rate

Sample Rate (Sampling Frequency)

The number of times per second that an analog audio signal is measured (sampled) when converting it to digital form, expressed in Hertz (Hz). Higher sample rates capture higher frequencies.

Codec

Codec (Coder-Decoder)

A software or hardware component that compresses (encodes) and decompresses (decodes) audio, video, or image data according to a specific algorithm, determining both the quality and file size of the compressed output.

Waveform

Waveform (Audio Visual Representation)

A visual graph showing how an audio signal's amplitude changes over time, displayed as a fluctuating line or filled shape that represents the loudness and dynamics of the sound at each moment.

Equalization

Equalization (Frequency Balance Adjustment)

The process of selectively boosting or cutting specific frequency ranges in an audio signal to shape its tonal character, fix problems, or match a desired sound profile.

Noise Reduction

Noise Reduction (Audio Cleanup)

The process of removing or reducing unwanted background sounds (hiss, hum, buzz, ambient noise) from an audio recording while preserving the desired signal such as speech or music.

Fade

Fade (Audio Volume Transition)

A gradual increase (fade-in) or decrease (fade-out) of audio volume over a specified duration, used to create smooth beginnings and endings for tracks or to transition between audio segments.

Compression (Audio)

Dynamic Range Compression

Reducing the volume difference between the loudest and quietest parts of an audio signal.

PCM

Pulse-Code Modulation

The standard method of digitally representing analog audio signals by sampling amplitude at regular intervals.

Mono

Monaural Audio

Audio reproduced through a single channel, where all sound comes from one source.

Spectrogram

Audio Spectrogram

A visual representation of audio frequencies over time, showing the spectrum of a signal.

Tempo

Audio Tempo

The speed or pace of an audio track, measured in beats per minute (BPM).

Reverb

Reverberation

The persistence of sound in a space after the original sound stops, simulated digitally for spatial effects.

Limiter

Audio Limiter

A compressor with a very high ratio that prevents audio from exceeding a set maximum level.

Delay

Audio Delay Effect

An effect that records and plays back audio after a set time interval, creating echo and rhythmic repetitions.

Noise Gate

Audio Noise Gate

A processor that silences audio below a threshold level, eliminating background noise between sounds.

Sidechain

Sidechain Processing

Using one audio signal to control the processing of another, commonly used to duck music under voiceover.

LUFS

Loudness Units Full Scale

A standardized loudness measurement reflecting perceived volume, used for broadcast and streaming normalization targets.

RMS Level

Root Mean Square Level

An average audio level measurement that better represents perceived loudness than peak level readings.

Peak Level

Audio Peak Level

The highest instantaneous amplitude in an audio signal, used to prevent clipping and set headroom.

Stereo Imaging

Techniques for widening, narrowing, or repositioning the perceived stereo field of an audio mix.

Frequency Spectrum

Audio Frequency Spectrum

The range of frequencies present in an audio signal, typically from 20 Hz (bass) to 20 kHz (treble) for human hearing.

Harmonic Distortion

Total Harmonic Distortion

The presence of frequencies that are integer multiples of the fundamental, sometimes added intentionally for warmth.

Nyquist Frequency

Half the sample rate, representing the highest frequency that can be accurately captured in digital audio.

Psychoacoustics

The study of how humans perceive sound, informing audio compression, spatial audio, and loudness standards.

Crossfade

Audio Crossfade

A smooth transition between two audio clips where one fades out while the other fades in simultaneously.

Audio Watermark

Audio Watermarking

Embedding imperceptible identifying data into an audio signal for copyright tracking and content identification.

Spatial Audio

3D sound technology that positions audio sources in virtual space around the listener using HRTF and head tracking.

Normalization

Normalization (Audio Level Adjustment)

The process of adjusting the overall volume of an audio recording so that its loudest point reaches a target level, ensuring consistent loudness across different tracks or recordings.

Mid-Side Processing

Mid-Side Audio Processing

A technique separating stereo audio into center (mid) and sides signals for independent processing.

Stereo

Stereophonic Audio

Audio using two independent channels (left and right) to create a sense of spatial width.