It might surprise some of you laptop makers to know that people actually use these things in their laps. I know, it's nutty. And when that happens, the speakers you put on the bottom of the machine get muffled. Put them up top or underneath the keyboard if you're trying to make it superthin.
Meanwhile, a lot of tablets place their speakers on the back edges, exactly where it's all too easy to block the sound with your fingers. Better-designed slates feature front-firing speakers, like the Samsung Galaxy Tab 2 10.1.