In the last section we saw that traditional speakers produce sound by pushing and pulling an electromagnet attached to a flexible cone. Although drivers all work on the same concept, there is actually a wide variety in driver size and power.
Tweeters are much smaller units, designed to produce the highest frequencies.
Midrange speakers produce a range of frequencies in the middle of the sound spectrum. And if you think about it, this makes perfect sense. This is harder to do with a large cone because of the mass of the cone. Conversely, it's harder to get a small driver to vibrate slowly enough to produce very low frequency sounds. It's more suited to rapid movement.