The stock horn system uses 2 horns, one High pitch and one Low pitch. On early models both horns are on the front of the car under the fog lights. However later on the PS horn was moved under the battery tray to make cutting the wire to it harder - it's shared between the security system and the standard steering wheel horn.
By removing the horn under the battery tray you have partially disabled your steering wheel horn - making it even more weeny sounding.
