FX-Sound is a 3D spatial audio backend for FiveM built on the Web Audio API, designed as a drop-in alternative to xSound. Every sound runs through a real Web Audio graph, receiving a PannerNode for true 3D positioning and a BiquadFilter for genuine low-pass muffling. Sounds inside sealed cars sound sealed, underwater audio sounds submerged, and indoor audio loses high frequencies through actual frequency filtering rather than volume reduction.

Positions, listener facing, and muffle cutoffs are smoothed toward their targets instead of hard-set, eliminating warble while driving, stutter while turning, and clicks when environments change. The system has no framework, database, or resource dependencies—other scripts drive it entirely through 21 exports, integrating under any existing music, radio, or ambience system.