A 1khz wave, often used as an effect for a flatline, test pattern, censorship, etc. This one more for effect (such as a movie) than a test tone. There's a nice stereo effect to make it more exciting, made by producing it as a sine wave for the left channel and a triangle for the right. The sine wave is at a slightly lower volume to make the 1khz fundamental the same volume level in both channels.
Author: Shanedk