Sound Test is an option that appears in the Super Smash Bros. games.
The Sound Test allows the player to listen to most of the music and sounds in the game. Players can listen to the voices of characters, stage music, and listen to other variety of sounds. In Super Smash Bros. and Melee, the Sound Test can be accessed through Data Mode; in Brawl, it can be accessed through either Data or Option Mode; in SSB4 it is located in the Vault and can also be accessed via the sound settings in Options. If the player leaves the Sound Test while a song is playing and goes back through the menus, the song will still play until it is overridden by another piece of music, or until the player enters the character select screen.
In each game, the methods of accessing the Sound Test differ:
Some pieces of music are unavailable in the Sound Test for unknown reasons; this includes the Fighter Select music in SSB, the Giga Bowser music in Melee, and the Cruel Brawl theme along with the winter version of Obstacle Course in Brawl. SSB4's Sound Test is missing some character voice clips, such as those of Duck Hunt. In Ultimate, Duck Hunt's noises are present, but those of Samus and Mr. Game & Watch are still missing.
In SSB, music and sounds do not have specific categories; from Melee onwards, they are organized by series for music, and by fighter for sounds. Generic, menu, and stage sounds each have a singular category, as do enemies, Poké Ball Pokémon, and Assist Trophies. Transforming characters like Sheik in Melee and Brawl, helper characters like Pikmin, and summonable characters from some Final Smashes and results screens (such as the Phantom Thieves of Hearts) are grouped under the main character's section (in aforementioned cases, being Zelda, Olimar and Joker respectively). Conversely, alternate costumes serving as alternate "characters" in SSB4 and Ultimate (such as the Koopalings or female Robin) feature separate sections from the default ones. In each game, Kirby's copy ability voice clips are unlocked after unlocking every base game fighter.
Starting in SSB4, unlike previous games, only music and voices are available; sound effects and victory themes are not. Additionally, unlike previous Smash titles, songs in Sound Test cannot be played indefinitely, instead fading out. The player can create a playlist by marking songs as favorites and can choose to have songs play in order or at random or to repeat a selected song once it is finished. Music tracks are indicated by a blue background, while voice clips are in green.
In Super Smash Bros. for Nintendo 3DS and Ultimate, the Sounds section can be set to play music even when the console is in sleep mode, with the L and R buttons used to skip between tracks. The sleep mode functionality can only be used if headphones are inserted.
The Japanese versions of SSB4 and Ultimate include credits for the voice actors of each character in the voice section. Notably, Kazumi Totaka and Masahiro Sakurai—the voice actors for Yoshi and King Dedede respectively—are credited here, but not in the actual credits. This is not consistent, however: the Inklings' voice actor, Yuki Tsujii, is not credited in the Sound Test or the credits. This is not present in any other version of the game, likely due to the use of uncredited union voice actors in the series' English dubs.
Another peculiarity specific to Ultimate is that, in the Japanese version, songs from English games use the localized English title rather than the original Japanese one. For example, the source game of the English version of Ashley's Song is listed as WarioWare: Touched!, rather than さわる メイド イン ワリオ. The same principle applies in reverse; in the English version of the game, the source game of Lost in Thoughts All Alone (JP) is listed as Fire Emblem: if instead of Fire Emblem Fates.
There are occasions where the Sound Test has sound clips that were never used in-game:
Not in Sound Test