ZIZZ STUDIO is a Japanese music unit formed in 2003. They've done a variety of work for the Nitroplus, inlcuding the soundtrack for the visual novel Saya no Uta and the image soundtrack to the Fate/Zero novel series.
Members:
Toshimichi Isoe (founder)
Ikuko Ebata
Kanako Ito
Kaori Tsutsui
Kunihiro Izumi
Masayoshi Murakami
Osamu Hata
Shigeso Sasaki
Syntaro Jimbo
Yasuhiko Tachibana
Yoh Ohyama
Yoichi Fujii