Simple Explanation

A step in sound where the pitch doubles (or halves) in frequency.

Concise Technical Definition

A frequency interval where the upper frequency is exactly twice (or half) the lower frequency—e.g., 500 Hz to 1,000 Hz.

Layman-Friendly Analogy

Like moving up a flight of stairs where each step doubles the height of the last one.

Industry Usage Summary

Octaves are used to describe frequency ranges in equalization, crossover design, and room acoustics. Audio filters and bandwidth specs are often defined in octave terms.

Engineering Shortcut

Frequency ×2 (or ÷2); standard unit for audio band division.

Full Technical Explanation

An octave is a logarithmic interval between two frequencies in which the higher frequency is exactly twice the lower one. For example, 250 Hz to 500 Hz is one octave, and 250 Hz to 1,000 Hz is two octaves. Octaves are used to divide the audio frequency spectrum into meaningful segments for analysis, equalization, crossover design, and acoustic treatment. In musical terms, an octave represents the interval between two notes of the same name (e.g., A2 to A3). In technical audio, octave bands (and fractional octave bands) are standard in spectrum analyzers, room tuning, and loudspeaker measurements. Lower octaves (e.g., 20 Hz–40 Hz) are particularly critical in subwoofer and room mode design.