In the world of hi-fi, stereo is considered the basic sound setup, and from there up, it is multichannel. As a rough analogy, when the automobile was invented it was first referred to as a horseless carriage, in deference to the then basic form of transportation, the obvious horse-drawn carriage. Now, the automobile is the base form of transportation, and succeeding forms of transportation are the airplane, spaceship and the like. No one makes reference to horse-drawn carriages although they exist (see Amish communities) as no one truly uses monophonic hi-fi systems. Hence, stereophonic is not multichannel.