There is indeed 2 systems, Pawnsensing and AiPerception. But once Aiperception is “finished” (it is finished but more user friendly) pawnsensing will be gone.
For Pawnsensing, to allow sound to be registered the component is PawnNoiseEmitter.
If i misundestood and you meant 2 system as “playsound” and “makenoise”, it does make sense because you don’t want your ai to react to any soundeffect you’re playing so you need to tell him wich sound to react to.