In an age where multi-channel receivers and equipment can be easily had, why do we stay with only two speakers?
Some of us have been around long enough to remember the days of Quadraphonic sound.
As its name implies, Quadraphonic sound utilized 4-channels of audio typically encoded on LP vinyl in a matrix system based on the work of musician and mathematician, Peter Scheiber. His basic formula utilized 90° phase-shift circuitry to enable enhanced 4-2-4 matrix systems to be developed, of which the two main leaders were Columbia's SQ and Sansui's QS Systems. (Scheiber eventually sued the Dolby Corporation for theft of his intellectual property).
The three most popular quadraphonic LP formats in the 1970s were SQ (Stereo Quadraphonic), QS (Regular Matrix) and CD-4 (Compatible Discrete 4) / Quadradisc.
These 4-channel systems enjoyed a brief flash of acceptance and then died out, never to be heard from again until the advent of home theater.
Seems people weren't all that interested in populating their living room with more than two speakers for the playing of music.
Though some of the most involving and emotionally satisfying musical presentations I have ever heard were multi-channel in nature, I still am in love with two-channel audio.
It might have been nice at one point in the development of home audio systems to have had buy-in from the world that rooms should be filled with speakers and recordings should all have many tracks.
That's not what happened and I for one am pleased with what we have.