First you need to unlock all the characters, then choose a stage while its loading have all the players that are playing hold down the L and R buttons when the you start the match you will hear diffrent music like the fire emblem theme in the temple stage or the battle theme in Pokemon stadium.
go to this link: http://www.ign.com/cheats/games/super-smash-bros-brawl-wii-748545
you dont unlock songs, you make them
You have to play them in"Tour Mode" to unlock them. Or you could enter the "Unlock all songs" cheat (God knows how).
No, you cannot unlock the songs with a cheat.
As a general answer, you can unlock songs from different Nintendo games, along with songs from Metal Gear Solid and Sonic the Hedgehog games. You can unlock different stages and stage parts for building your own stages. You can also unlock characters to fight as, trophies, stickers that can power you up in the adventure mode, and assist trophies that can help you in brawls. You can even unlock demos for different games, and a list of Nintendo games.
I'v played a bit. The only things to unlock seem to be tutorial vids. Sorry. The game designers didn't give us any unlock-able songs. No you Can't Unlock songs
Smash Mouth songs can be heard in the movie Shrek.
You don't unlock new songs.
all songs unlocked
You have to unlock it by playing other songs first or get the cheat code to unlock all the songs.
269 or 279.
If you get the highest score on normal you unlock things sometimes costumes, rabbits, games and (rarely) additional songs If you get the highest score on normal you unlock things sometimes costumes, rabbits, games and (rarely) additional songs If you get the highest score on normal you unlock things sometimes costumes, rabbits, games and (rarely) additional songs