Bass Traps treat corners of rooms, including wall/floor and wall/ceiling, if done correctly. Bass traps are panels that straddle the corners, just like in recording studios, as bass collects in corners, which skews the overall frequency response in a room. Many think this only applies to recording studios, which is untrue, the same applies to home applications. Superchunks are the same material, but they fill the corner from floor to ceiling versus panels stradleing the corners. First reflection panels are acoustic panels that are placed in the "first reflection" points on your walls/ceilings. This helps tame the non-directional sound coming from the speaker, so the sound is not skewed and more tight/detailed.
Think about when you clap your hands loud in a room with bare walls and floors, you hear terrible echos. With treatments, you don't.
