The term 'Better Than Stereo' can be summarized by the crossword solution of the word 'QUAD', which is a four-letter word. Quadraphonic sound, also known as quadrophonic sound or simply QUAD sound, is a type of surround sound technology developed in the 1970s. It uses four channels in which sound is separated and directed to four different speakers to create a more immersive sound experience than traditional stereo sound. Quadraphonic sound was popular in the 1970s but has since been replaced by more advanced surround sound technologies.