Can you hear me ... No, not going to say it.
The sound card comes out next, and nearly last.
MacBook Air: In the right-hand inset frame, we see the location of the Air sound "module", and we see that it is about the same size, but it includes the speaker. On the left, we see a better picture of the "module".
I was surprised that Apple used mono sound here, when all others have tried to sharpen the "multimedia experience" in notebooks. I have heard that it sounds quite good, though I have not heard it my self.
Maybe some of the thought process here was that most users who want great sound would get an external system anyway, so why waste the weight/space/engineering?