It is unclear if the sound like the rushing of a mighty wind (Acts 2:2) or the sound of people speaking in different languages is what drew the crowd to the house or room where the believers were. Likely it was a mixture of the two. It could also be that the believers themselves left the room to go out into the street.1 The fact that the crowd heard different languages and understood what was being said suggests that the believers did not all speak at the same time.2 Most probably it was the twelve apostles who took the lead in speaking to people as they arrived or walked by (see Acts 2:14).
6 And at this sound the multitude came together, and they were bewildered, because each one was hearing them speak in his own language.