Johnny Gioeli is an American singer who, besides singing for Crush 40, also sings in his own band Hardline, and for the German guitarist Axel Rudi Pell. He has also sung for several other artists, such as Accomplice and Doug Aldrich (Whitesnake), the latter being the one who got Jun in contact with Johnny when he needed a vocalist for the Sonic Adventure soundtrack.
Jun Senoue is a Japanese guitarist who started playing guitar at the age of 15. He joined SEGA in 1993, after he graduated from college with a degree in economics, as a video game composer. The first SEGA game of which Jun composed the soundtrack was Dark Wizard, followed by Sonic The Hedgehog 3. Ever since he has composed several SEGA videogame soundtracks, but he is most known for his work for the Sonic franchise. Besides working with Johnny in Crush 40, Jun also worked with several other artists such as Eric Martin (Mr. Big), Tony Harnell (TNT), and Ted Poley (Danger Danger).