This pack will replace the stock explosion sounds you would normally hear, whether it be a granade, panzerschreck/bazooka or rifle grenades. Play the sound clip provided by the link below. I find these explosions not as loud as the stock sounds but more realistic. My favorite is when a panzerschreck/bazooka is fired past you and explodes...omfg!
Trappa's Explosive Explosions...
Once d/l'ed extract the files. You'll see two folders, scripts and sound.
The scripts folder goes here...
C:\Program Files\Steam\steamapps\Account Name\day of defeat source\dod\scripts
The sounds folder here...
C:\Program Files\Steam\steamapps\Account Name\day of defeat source\dod\sound\weapons
Enjoy...