Masashi Hamauzu
Production began following the release of "" in 2006; that game's writer Hiroki Chiba acted as both director and writer for "Sigma Harmonics". Other returning team members included producer Yoshinori Kitase, artist Yusaku Nakaaki, and composer Masashi Hamauzu. The premise was inspired by Chiba's liking for Shōwa period mystery writers. The team used tools supplied by CRI Middleware to both fit all their planned content on the DS cartridge and incorporate Hamauzu's music with minimal reduction in quality.