In this tutorial we use a tool called BassDrop which is provided free.
First we recommend preparing your sound file for World at War as the sound tool doesn't work with all audio formats, so please follow this tutorial first [World at War] Converting Sounds.
First you need to determine whether or not the sound is for the FF's or the IWD's, if it's a gunsound or an fx, check the Loaded (FF) setting, otherwise use the Streamed (IWD) setting. Next simply drag and drop your already made audio files onto the UI and the'll convert with a _BO suffix.
Note: You can't natively play these files.
After that you can use those files in your mod.
Again, just drag and drop Black Ops sound files onto the UI and they will convert back with a _PCM suffix. These files can be edited and played natively on your PC.