Koichi Ishii | Koichi Zenigata | Koichi Wakata | Koichi Wajima | Koichi Sakamoto | Koichi Nakamura | Koichi Domoto | Saiichi Sugiyama | ''Ruddock with Koichi Tohei Sensei in Iidabashi dojo (photo by Henry Kono)'' | Noriaki Sugiyama | Koichi Yamaguchi (bicycle framebuilder) | Koichi Yamaguchi | Koichi Tohei | Kōichi Tōchika | Koichi Tanaka | Kōichi Tabuchi | Koichi Sasada | Koichi Ohata | Koichi Nakano | Kōichi Morita (songwriter) | Kōichi Morita | Koichi Kato | Akiko Sugiyama |
In their early years they sang Japanese covers of standards, foreign hits, and Japanese folk songs; then they began singing originals, written by their producer, Hiroshi Miyagawa, and such songwriters as Koichi Sugiyama and Rei Nakanishi.
In 1991, Enix released a set of videos featuring Koichi Sugiyama conducting the London Philharmonic Orchestra performing the soundtrack in Warwick Castle, along with clips of acting.