File created by cfxr ("Cocoa sfxr"), a Mac sound effects program that was ported from the original sfxr Windows program; saves settings for one or more sound effects in an XML format; used for storing randomly generated sound effects.

CFRX files are often used for storing sound effects for video games. They are saved using XML formatting instead of the binary .SFS format used by sfxr. But, they can still be exported to .WAV files like sxfr. The cfxr program randomly generates the levels across various sound settings each time the user selects a new sound. Saved CFXR files store sound information such as the the attack time, sustain time, decay time, vibrato, phaser offsets, and filters.