Masaaki Endoh is a Japanese singer-songwriter who is prominent in the area of soundtracks for anime and tokusatsu productions. He is one of the founders of the Anison band JAM Project and has been a regular member ever since its inception in 2000. His nickname is the "Young Lion of Anison" and he goes by the motto "Always Full Voice".

JAM Project are a Japanese anison band founded on July 19, 2000, by anison singer Ichirou Mizuki. The band is composed of many vocal artists well known in the anime music industry. Aside from the many anime, tokusatsu, and video game theme songs the band has performed together, each member is famous for their own solo performances of Japanese theme songs. JAM Project is known to worldwide audiences for their theme music contributions to Garo and One-Punch Man.