Karaoke Kids

A popular game using karaoke is to randomly type in a number and call up a song, which participants take a turn to try to sing as much as they can. In some machines, this game is pre-programmed and may be limited to a genre so that they cannot call up an obscure national anthem that none of them can sing. This game has come to be called "Kamikaze Karaoke" or "Karaoke Roulette" in some parts of the United States and Canada.[citation needed]
Many low-end entertainment systems have a "karaoke mode" that attempts to remove the vocal track from regular audio CDs. This is done by center removal, which exploits the fact that in most music the vocals are in the center. This means that the voice, as part of the music, has equal volume on both stereo channels and no phase difference. To get the quasi-karaoke (mono) track, the left channel of the original audio is subtracted from the right channel. The Sega Saturn also has a "mute vocals" feature that is based on the same principle and is also able to adjust the pitch of the song to match the singers vocal range.
The crudeness of this approach is reflected in the often poor performance of voice removal. Common effects are hearing the reverberation of the voice track (due to stereo reverb being put on the vocals), and also other instruments that happen to be mixed into the center get removed (snare/bass drum, solo instruments), degrading this approach to hardly more than a gimmick in those devices.