Simple Explanation

A system where the phase response can be perfectly predicted from its amplitude response.

Concise Technical Definition

A system in which amplitude and phase are uniquely related, allowing phase to be fully determined from the magnitude response alone.

Layman-Friendly Analogy

Like knowing someone’s full schedule just from seeing their commute time—one tells you everything about the other.

Industry Usage Summary

Minimum-phase behavior is desirable in filters and loudspeakers because it ensures predictable phase alignment and time-domain behavior. Common in analog and DSP filter design.

Engineering Shortcut

Phase is mathematically derivable from amplitude; all poles and zeros in left-half s-plane.

Full Technical Explanation

A minimum-phase system is one in which the phase response is uniquely determined by the amplitude (magnitude) response, meaning there is a fixed mathematical relationship between them. This occurs only when all the zeros of the transfer function lie in the left half of the complex s-plane (in Laplace-domain analysis), making the system causal, stable, and invertible. In audio, minimum-phase filters are favored because they introduce the least possible phase shift for a given magnitude response. This property also allows reconstruction or prediction of the phase response from measured amplitude data—useful in loudspeaker measurement, room correction, and DSP filter design. Minimum-phase systems preserve time coherence better than non-minimum-phase systems, making them crucial for accurate signal reproduction.