Here's a video from the recording of Argento Soma ten years ago. It features some amazing names: Kuwashima Houko, Houshi Souichirou, Koyasu Takehito, Nakata Jouji, Inoue Kikuko, Takahashi Hiroshi, Horie Yui, and others.
We get a glimpse of what a real anime recording studio is like, and a touch of the seiyuus' dance back and forth to the mics:
ID key: Kuwashima Houko (in purple/black), Houshi Souichirou (in red/white check shirt), Koyasu Takehito (in black v-neck), Nakata Jouji (black shirt with white stripe on sleeves), Sayuri (face blocked by script), Inoue Kikuko (red dress), Kawasumi Ayako (deep v-neck black blouse), Chafurin (fuzzy hair and jowls), Takemura Hiroshi (Japanese jacket and ponytail), Takada Yuuji (pale western shirt), Takahashi Hiroshi (grey STP shirt), Horie Yui (in red, with long hair). Interview with Houshi Souichirou and Kuwashima Houko.