The pilot's headphones will have a 3-D sound system so that the voice of another crew member will seem to come from that person, to avoid confusion. Audio "earcons" will signal certain events — a sucking sound will warn of fuel exhaustion, for instance. Speech input will be used to control non-essential systems.
—Lamont Wood, "Fashion takes high-tech turn," The Chicago Tribune, March 4, 2002

He is editing a special edition of the journal Human-Computer Interaction, on the use of non-speech audio in the computer's output. Small but meaningful sounds have become known as 'earcons,' by a punning analogy with 'icons.' To those who doubt their importance, Buxton says: 'all you have to do play a video game like PacMan. Turn the sound off and your score will go down. It clearly contains information that is valuable.'
—Tony Durham, "The human touch — Professor Bill Buxton's hopes for improvements in the man-machine interface," The Guardian, August 4, 1988