My right speaker was distorting very badly.
Fantastic. Couldn't have been easier. The tools and guide are fantastic. Replacing the speakers is a pretty simple task when you have the correct tools.
Be very careful when tightening the screws. They are small and somewhat soft and you can strip the heads pretty easily. You don't need as much torque as you think.
MacBook Air 11" (Late 2010-Early 2015) Right Speaker
T5 Torx Screwdriver
P5 Pentalobe Screwdriver Retina MacBook Pro and Air