The Japanese versions of the game are developed by Konami themselves. The gameplay also differs significantly. Rather than a game per se, it is merely a Karaoke system for the PlayStation 2, with no judgements.
The game does not attempt to understand the singer's words, but instead detects their pitch. As such, singers can hum to a song or sing different lyrics without penalty. The game adapts to the player singing in a different octave than the song, to accommodate players whose vocal ranges do not fit the song.
The songs in the game are covers (not performed by the original artists, but similar to the originals) of pop hits frequently sung in karaoke bars. This contrasts with the SingStar series from Sony Computer Entertainment Europe, which features only original artist recordings along with the music videos, where available.
Each song is divided into approximately 30 to 50 "phrases". A meter will fill up and turn from red to green for each phrase, based on how well the player sings the right notes; if the player can fill the meter to green, (s)he will score more points, and getting several greens in a row will create a "combo" and award a 2x score multiplier until the player fails to make green on another phrase. This blue meter resembles how long you should hold the note for and at what pitch. The game can be set at higher difficulties which make this meter larger and require the player to hit the right notes more precisely to fill it to green.
Since maximum scores for each song are normalized 50,000 regardless of difficulty, overall scores on songs can be compared. To achieve the gold record for a song, 12,500 points must be achieved. To achieve the platinum record for a song, 20,000 points must be achieved. Winning records will unlock additional characters, outfits, and songs. In Karaoke Revolution Party and Karaoke Revolution Presents: American Idol, 50,000 points (a perfect score) earns a diamond record. In Karaoke Revolution Presents: American Idol Encore the point system was changed so that 60,000 points gives a platinum record for a song and 100,000 points is a perfect score (diamond record).
Karaoke Revolution Volume 2 introduces a "medley mode" which challenges the player to sing a string of short clips from various songs.
Karaoke Revolution Volume 3 introduces "duet mode" which lets two singers play simultaneously. It also revised scoring so that perfect performances result in exactly 50,000 points (with the exception of the Jackson 5's "ABC").
Karaoke Revolution Presents: American Idol utilizes American Idol judges, commentary, and stages.
The North American version of Karaoke Revolution was released in November, 2003 in a bundle with the Logitech headset attachment. The game was sold without the headset in February, 2004. The European version of the game, titled Karaoke Stage, was released on April 22, 2005. 'Karaoke Stage 2' contains the same songs as 'Karaoke Revolution Party'.
Karaoke Revolution Presents: American Idol was released in North America on January 2, 2007. The PlayStation 3 version is the only one that has all downloadable songs available on the PlayStation Network marketplace. The Xbox 360 version has six songs discontinued from the Xbox Live marketplace for undisclosed reasons.
Karaoke Revolution Presents: American Idol Encore was released in the United States on PlayStation 2, Wii, and Xbox 360 on February 5, 2008, and was released to Canadian retailers on February 17, 2008, with the PlayStation 3 version released in North American on March 4, 2008.
Karaoke Revolution Presents: American Idol Encore 2, the direct sequel to Karaoke Revolution Presents: American Idol Encore is scheduled for release on November 18, 2008 in the United States on PlayStation 3, Xbox 360 and Wii.
Four different microphones were released for the game:
The SingStar microphones are not compatible with Karaoke Revolution though un-officially, do work on the PS3 version of the game.