Simple Explanation

A measure of how much a speaker or system delays different frequencies—especially noticeable in the tightness of bass.

Concise Technical Definition

The rate of change of phase with respect to frequency; mathematically, the first derivative of phase versus (linear) frequency.

Layman-Friendly Analogy

Like runners finishing a race at slightly different times, group delay shows how some frequencies arrive late.

Industry Usage Summary

In audio systems, excessive group delay—especially in the bass region—can result in “loose” or “boomy” sound. It is affected by filters, crossover designs, and cabinet types.

Engineering Shortcut

d(phase)/d(frequency); measures signal timing skew across spectrum.

Full Technical Explanation

Group delay is a measurement of how much a system delays the envelope of different frequency components of a signal. Defined mathematically as the first derivative of phase shift with respect to frequency (dφ/df), group delay reflects how phase changes across frequency. In a system with linear phase or constant group delay, all frequencies experience the same time delay, preserving waveform shape. However, in real-world loudspeakers and filters, group delay often varies, particularly in the low-frequency region, where added filters (like high-pass protection) and ported enclosures can introduce delay. This variation can affect perceived sound quality, causing bass to sound smeared or less “tight.” Systems with minimum phase characteristics often aim to control group delay for better clarity and timing.