Simple Explanation

How easily a speaker’s suspension (the flexible parts) moves back and forth.

Concise Technical Definition

The measure of the flexibility of a speaker's suspension system, specifically the inverse of stiffness, usually represented as Cms (compliance of the mechanical suspension).

Layman-Friendly Analogy

Like the softness of a trampoline—more compliance means it’s bouncier, less means it’s stiff.

Industry Usage Summary

Commonly referenced in Thiele/Small parameters when designing or evaluating speaker drivers. A higher compliance generally indicates a softer suspension, which affects resonance frequency, enclosure design, and bass performance.

Engineering Shortcut

High Cms = soft suspension = lower resonant frequency; low Cms = stiff suspension = higher resonant frequency.

Full Technical Explanation

Compliance refers to how easily the moving parts of a loudspeaker (usually the cone and voice coil assembly) return to their resting position after being displaced. Measured as Cms in meters per newton (m/N), it is the inverse of stiffness (Kms). High compliance means a more flexible suspension and typically corresponds to lower resonant frequency (Fs), influencing the driver's low-frequency extension and suitability for certain types of enclosures.