After disassembling the base 13-inch MacBook Pro model without the Touch Bar, teardown wizards over at iFixit have now taken apart Apple’s Touch Bar-equipped 13-inch MacBook Pro. From the inside, it’s an entirely different computer with a totally different design that has more in common with its 15-inch brethren. Among other things, the teardown analysis has found that the external speaker grilles in the top half of the case exist mostly for “cosmetic” purposes.
That's because the improved sound is being projected from a pair of air vents on the sides of the case. By comparison, the base 13-inch MacBook Pro without the Touch Bar does push sound through the speaker grilles as it lacks the air vents.
Other differences between the 13-inch MacBook Pro with Touch Bar and its cheaper 13-inch variant that lacks the Touch Bar include a differently laid out internal components to make room for the Touch Bar itself which, by the way, is hard to replace.