Entity Sound Features (ESF)
What is this mod?
ESF is a mod that allows the variation of an entity's sounds based on the ETF / OptiFine .properties format.
ESF also adds extra sound related utility to ETF and EMF in the form of sound properties and sound animation functions
how?
For instructions and an example of how to variate existing played sounds see this guide
For instructions on how to use the added sound related utilities for ETF and EMF see this guide