Simplify the following text for a Grade 6 native English-speaking person.
Original: After graduating from high school , the California natives began to take their musical interests more seriously , recruiting Joe Hahn , Dave `` Phoenix '' Farrell , and Mark Wakefield to perform in their band , Xero .
Simplified: After high school , they started to get serious and added Joe Hahn and Dave `` Phoenix '' Farrell . When they could not get a contract from a major music company , Mark Wakefield quit .