Sound Attract NPC

For a Steath Game…how I can make my Npc notice a sound if he is in a certain area? In UE3 I could use a TOGGLE to able and disable a trigger volume without destroy it…this is possible?

Sound detection is built into UE4. Go to the components menu of your blueprint and add a PawnSensingComponent. On the settings menu for the component select to add the sound detection even to your blueprint. You can create noises using blueprints as well.