sentences:  The series initially used mostly cover versions of songs created by WaveGroup Sound, but most recent titles feature soundtracks that are fully master recordings, and in some cases, special re-recordings, of the songs.Later titles in the series feature support for downloadable content in the form of new songs.In 2005, RedOctane, a company specializing in the manufacture of unique game controllers, was inspired to create "Guitar Hero" based on RedOctane's experience creating hardware for Konami's "Guitar Freaks" arcade game.