Sound Horizon

Sound Horizon is a Japnaese music composition unit formed in 2001. They describe themselves as a "fantasy band" and have released works that closely resemble classical suites.Their songs often revolve around historical events and classic fairytales.

Its members are:

~ Kamanaka Yasuo (Revo) 
~ Ebisu Hirokatsu
~ Fujimoto Ken'ichi
~ Fukami Rica
~ Gen Ittetsu Strings (string instrument orchestra)
~ Hasegawa Atsushi
~ Ike Nelson
~ Ishigame Kyouko
~ Ishikawa Naomi
~ JIMANG
~ Joelle Strother
~ Kana Strings (Itou Kanako/伊藤 佳奈子)
~ Nakano Ritsuki
~ Nantou Ryouji
~ Ochiai Tetsuya
~ Oda Kaori
~ Oosako Kyouko
~ Remi (a.k.a. Tanaka Remi)
~ Saitou jake Shingo
~ Saka Tomotaka
~ Sakagami Ryou
~ Tamura Shigeru
~ Uesato Hanako
~ Watanabe Fire
~ YUUKI

Japanese : https://ja.wikipedia.org/wiki/Sound_Horizon
VGMDb: http://vgmdb.net/artist/3637