@Wetrix indeed. But today I wanted to smell the tires and get a full immersion, so I ended up buying a day pass to the entire circuit area for S$138. I can't get to the grand stands, but there are free stands with good visibility.
Tomorrow I made a reservation at restaurant with a view over the track at the time of the qualifying race.
Then, on Sunday, I guess I'll watch the real race on a big screen :-)
@Wetrix yeah, even the practice is unbelievably loud!