Play as Goku 4
At the title screen (with Goku on the right and the instructions for entering the sound test mode) press Right, Left, Down, Up, Right, Left, Down, Up. You should hear a tone. Next, press Triangle FIVE times, then press X 9 times. If done correctly another tone will sound and the menu screen will now have a cool picture of Super Saiyajin Level 4 Goku.