The music of Super Smash Bros. (Wii U and 3DS) is made up of a very large collection of tracks, doubling the size of Brawl's collection. Most of the tracks from the first three games remain the same, though some have been remixed. In Super Smash Bros for Nintendo 3DS, only two songs are available for each track due to memory limitations. For Super Smash Bros for Nintendo Wii U however, the Sound Test returns from Brawl, and most tracks are available from the start when selecting the option, though some require certain criteria to be unlocked.