This mod adds reverberation effects to different environments and an attenuation mechanic to all blocks. All of this allows for sound-proof rooms, reverberating booms from a hovering ghast, and most importantly: eliminating the ever present moan from that zombie eight solid blocks below you!

BSM Installation/Usage:

I recommend creating a backup of the minecraft 'bin' folder first!

Update to the latest LWJGL release or nothing will work. (Note: once these steps are completed they do not need to be repeated when updating BSM or Minecraft unless you use the "Force Update" option from the launcher).
1. Download the latest LWJGL release for your operating system at lwjgl.org (update tutorial here).
2. Extract/copy the contents of the zip file to the 'bin' folder located in the main minecraft directory.
Download the latest Better Sound Mod version zip-file here and copy all of the class files to 'Minecraft.jar' with your preferred archive program.
Delete the 'META-INF' folder located in 'Minecraft.jar' if you haven't already done so.
You're done! Go play in you're newly acoustically attenuated playground!

Mod Compatibility:

AudioMod: Yes. Install BSM after AudioMod.
Optifine: Yes.
Minecraft Forge: No (for now). Installing BSM after Forge will (mostly) work, but may cause crashes/irregularities with certain mods installed.
MAtmos: Yes.
GLSL Shaders: Yes.

BetterSound Mod