"Tatsuya Yoshida, born in Kitakami, Iwate is a Japanese musician; drummer and composer who is the only consistent member of the renowned progressive rock duo Ruins, as well as Koenji Hyakkei. He is also a member of the progressive rock trios Korekyojinn and Daimonji. Outside his own groups, Yoshida is renowned for his tenure as drummer in the indie progressive group YBO2, a band also featuring guitarist KK Null, whom he also joins in the current line up of Zeni Geva and he has played drums in a late edition of Samla Mammas Manna. He has been cited as "[the] indisputable master drummer of the Japanese underground". Along with his participation in bands, he has also released several solo recordings."

"Born November 17, 1963, in Morioka, Iwate prefecture, Mitsuru Nasuno (那須野満, Nasuno Mitsuru) started playing the electric bass at the age of 17, and soon began playing rock music with friends from his high school.

In 1981 Nasuno moved to Kyoto to attend Kyoto Sangyo University, where he joined student bands and played in a variety of pop styles - hard rock, new wave, funk, and so on. He even joined a university big band, and for a time took double bass lessons in order to play big band jazz.

After graduation, Nasuno played in several rock- and funk-oriented bands, such as Schwarz. It was during this period (in 1989) that he met drummer Yasuhiro Yoshigaki, who, with guitarist Kazuhisa Uchihashi, was planning to form a trio that would have a sound similar to that of the group Power Tools (Bill Frisell, Melvin Gibbs, and Shannon Jackson). Yoshigaki invited Nasuno to join him and Uchihashi, and about a year later - in April 1990 - the trio Altered States gave their first concert, in Kyoto.

For the first three years after the group formed, Nasuno felt unsure about how to adapt his playing style to the ideas of the other members, and he often thought about quitting; but eventually he overcame these difficulties and hit his stride. At first the pieces played by Altered States were mainly based on Uchihashi's compositions. Over time, improvisation made up a greater and greater proportion of their music, and now their live performances are entirely improvised.

Soon after the launching of Altered States, Nasuno became very interested in noise music. In 1993 he and drummer Toru Sanjo formed a band called the Mugamps, which made extensive use of odd rhythms and noise. The band remained together for about a year. In the same period, Nasuno was also a member (for a year) of the underground music band Amaryllis.

Through his activities with Altered States, Nasuno came to be known on the improvised music scene in Japan. In 1994 he became a member, along with Yoshigaki and Uchihashi, of turntable and guitar player Otomo Yoshihide's group Ground-Zero. The group's other members at the time were drummer Masahiro Uemura and bassist Masaki Shimizu (soon to be replaced by sampler player Sachiko M). In '97, Nasuno joined drummer Akira Sotoyama's group Manzokuyama (the other members of which are sax player Naruyoshi Kikuchi and guitarist Akihiro Ishiwatari); and in '98 he participated in drummer Tatsuya Yoshida's trio Korekyojinn, with guitarist Natsuki Kido.

In 1996, Nasuno moved his base of activity from Kyoto to the Tokyo area. In June of '98 he brought together five younger musicians (an alto sax player, two guitarists, a drummer, and a percussionist) and relaunched his band the Mugamps, whose first gig, in Tokyo, featured two guest musicians (a guitarist and a keyboard player).

Since 1993, as a member of Altered States and Ground-Zero, Nasuno has made several concert trips to Europe ('93, '95 and '97) and North America ('95). Among the musicians he has played with are Kazutoki Umezu (reeds), Koichi Makigami (voice), Seiichi Yamamoto (guitar), Atsushi Tsuyama (bass and guitar), Yamatsuka Eye (voice), Tenko (voice), Shuichi Chino (keyboards), Michiyo Yagi (koto), Yumiko Tanaka (shamisen), Hoppy Kamiyama (keyboards), Jon Rose (violin), Ned Rothenberg (reeds), Samm Bennett (percussion), Martin Tetreault (turntables), Leonid Soybelman (guitar and vocal), Jane Scarpantoni (cello), Hugo Fattoruso (keyboards), and Thomas Buckner (vocal)."