Two-way speakers consist of a woofer and a tweeter, and three-way speakers have a woofer, tweeter and mid-range component. The mid-range component is designed for sounds in the 160 Hz to 5.2 KHz range, such as the sounds of a saxophone, human voice or trumpets.
Both two-way and three-way speakers can be housed together in one case or purchased as a set of individual speakers. Sets of individual speakers are known as component speakers, and each speaker has a specific audio range. For example, a woofer generally has a range of 3 KHz to 20 KHz, and a tweeter has a range of between 30 Hz and 160 Hz.
Two-way speakers are called coaxial speakers, and three-way speakers are commonly referred to as tri-axial speakers.