Here's a picture (this isn't my car, I found this on Google):
You can see the right-most exhaust tip is connected to the actuator. I'm not sure if the muffler has two chambers (one with less restriction) or if just opening an extra exhaust outlet increases the airflow and sound. An expert would have to tell you, and I am not one.
(A side note: That guy accidentally photographed his head. Lol.)