Mansaku Kimura (木村万作) is a Tokyo-born drummer whose credits run from 1980 to 2018 and sit mostly on the fusion side of Japanese jazz, most of them in Prism, the band of the guitarist Akira Wada. Discogs lists 86 entries for him, every one of them as a sideman; no album carries his name as leader. Some listings, including English Wikipedia's Prism member list and a number of Discogs credits, print his name as Satoshi "Mansaku" Kimura.

He was born on 30 December 1955 in Tokyo, according to the biography Sony Music Japan publishes for the Far East Club Band, and Wikidata narrows the birthplace to Koto ward. He went to Waseda University (Wikidata also records Waseda's attached junior and senior high school), and it was there, in 1978, that he met the pianist Ichiko Hashimoto. Sony dates the start of his professional career to that meeting. In 1980 he took part in the recording of Colored Music, the project of Hashimoto and the bassist Atsuo Fujimoto; his Sony and Sabian biographies both give 1980 for the sessions, and the album was issued on the Better Days label in 1981. Japanese Wikipedia says he worked as a studio musician from then on.

The next few years show him in the middle of Tokyo's fusion scene. On Akira Wada's solo album Yellow Moon (TDK, 1984) he is one of three credited drummers, alongside Jun Aoyama and Toru Suzuki. On Hashimoto's Beauty (Domo, 1985), produced by Kazumi Watanabe, he is the drummer, and he plays drums and percussion on the following year's Beat Jazz by Atsuo Fujimoto's Beat Jazz (Better Days, 1986), on which Hashimoto plays piano and sings. A 2004 Solid Records compilation of Japanese jazz and funk, Shibuya Jazz Clash, credits him on two tracks: "I Love Your Music," the Beauty piece, with Kazumi Watanabe, Fujimoto and Hashimoto, and "Heart Beat." In 1986 and 1987 he appears on three tracks of MALTA's Sparkling (JVC) and on one track of My Ballads, in each case alongside the bassist Ken Watanabe, the guitarists Toshiki Nunokawa and Katsutoshi Morizono, and the keyboardist Masahiro Sayama. He also drums on Heart Cocktail Vol. 3 (1987), the soundtrack album of an anime series, credited to Tony's Show.

Prism is the center of the career. The band went on hiatus in 1984, and Japanese Wikipedia says Kimura joined it in 1985, when activity resumed, as a support member, and was made a full member in 1988. Wikidata also dates his membership from 1985. He is the drummer on Nothin' Unusual (TDK, 21 June 1985), which was recorded at Onkio Haus in Tokyo between 9 March and 21 April of that year, with Wada, Ken Watanabe and the keyboardists Jun Fukamachi and Yoshikazu Matsuura. Discogs lists his kit on that album as Pearl drums, Paiste cymbals and Simmons electronic drums. Dreamin' followed in 1986, with the piece "Take Off," which English Wikipedia says was used in a Mild Seven commercial that year, and then The Silence of the Motion in 1987. By the early 1990s Prism was working as a trio of Wada, Watanabe and Kimura, the lineup of A Personal Change (Apollon, 1992).

From Mother Earth (Emotion, 1990) onward he is also credited as a composer. Discogs lists him as writer or composer of two tracks on each of Mother Earth, Rejuvenation (1991), A Personal Change (1992), In the Last Resort (2001) and the 2003 album mju; three on Whiter (1997), among them "Spiral Blues"; four on Blue... (2007); three each on Invite (2009) and Palace in the Sky (2011); and two on What You See (2017), "Lights in the Distance" and "Struggling Blues." The 2005 set Sanmi Ittai adds two more entries for pieces that already existed. That is 27 composer entries across eleven Prism releases, some of them credits for the same piece on more than one record. Two of the band's albums from the 1990s are live records: Prism Jam (Eastern Gale, 1995), recorded in Kobe on 4 and 5 March 1994, where Kimura shares the drum chair with Shuichi "Ponta" Murakami, and Uncovered (1995), recorded at Roppongi Pit Inn in March and December 1994, on which Discogs credits him with drum programming as well as drums.

Ken Watanabe left the band at the turn of the millennium, and the bassist Jiro Okada replaced him. Japanese Wikipedia says that from then on Kimura was Prism's longest-serving member after Wada. The trio recorded In the Last Resort (Turnon-C, 2001). In 2003 Universal reissued the band's early albums, and Prism recorded Present I, Present II and mju for the company; Present II collects new versions of pieces from 1977 to 1987, with the keyboardist Daisaku Kume among the guests. The three-disc Sanmi Ittai (Cosmos Records, 2005) pairs Kimura with Wada and Okada, and Billboard JAPAN's catalogue entry describes the band as a jazz and fusion group made up of exactly those three men. For its 30th anniversary Prism made the album Blue... (Beat On Beat, 2007), with guests including Kume, and played a concert at Shinjuku FACE on 7 July 2007 that was issued on DVD. The keyboardist Cheru Watanabe joined in 2013, and the later albums, Invite, Palace in the Sky, Mode : Odd (2013), Celebrate and What You See (both 2017), were all made for Beat On Beat. Discogs credits him on drums on every one of them, with percussion on most. In all, it credits him on 25 Prism releases, from 1985 to 2017. Wada fell ill at the end of 2018 and passed away on 28 March 2021.

Beside Prism he kept a second career as a band and session drummer. Sony's biography says he joined Toshiki Nunokawa's fusion group VALIS in 1988; the Discogs credits are five Nunokawa Valis records, Valis (Ninety-One, 1991), Under Construction (Videoarts, 1993), Ali's Dance (Picaia, 1995), Live - Hieroglyph (Ninety-One, 2002, recorded at Blues Alley in Tokyo on 13 and 14 September 2001) and The Last Gift (Shiosai ZiZO, 2003). He plays drums on the Latin-fusion records of the pianist Naoya Matsuoka, Majestic (Warner Bros., 1988), Songs and Days (1989), June, July, August -Summer Pieces- (1990) and Un Jour... (2001), on three albums by Hiroshi Kubota Project 4our, a keyboard-led fusion project (1987 to 1989), on two organ-fusion albums by Kiyomi Otaka, Third Hand (1998) and Ambition (2000), and on the pianist Motokazu Shinoda's Pivot (2000), Floating Colors and Foresight (both 2003). On the saxophonist Akira Sakata's D.D.T. (Victor, 2008), a record billed to Sakata and Akira Emoto, he drums on one track, "Senaka Made 45 Fun."

The other large share of his work is with the singer Kazumasa Oda. Japanese Wikipedia identifies him as a member of Far East Club Band, Oda's backing band, and Sony's profile lists him as its drummer, with the saxophonist Mitsuhiro Sonoyama, the bassist Kaoru Yamauchi, the keyboardist Naoki Kurio and the guitarist Masahiro Inaba. The band's instrumental album Another Moonlight (Ariola Japan, 24 April 2002) lists him on drums and percussion, and Discogs credits him on drums or cymbals across a series of Oda albums and compilations from 1995 to 2014, among them Looking Back (1996), Looking Back 2 (2001) and Oda Biyori (2014). He has also drummed for pop acts, among them Chisato Moritaka (Hijitsuryokuha Sengen, 1989), Morning Musume (1998 to 2001) and Aya Matsuura (2004). His Sabian Japan artist page adds a list of names he has worked with, including the singer Marine, the jazz singer Kimiko Itoh, Hi-Fi Set, Tokiko Kato, Shogo Hamada and Miyuki Nakajima. That list is his endorser's, not a credit list, and no specific recording with several of those names has been confirmed.

Away from the bandstand he teaches on video. Japanese Wikipedia lists two instructional titles, Fill-in Standard Phrases: Rock Drumming Edition (Rittor Music, 20 February 2003) and Groove: Drumming Basic Method (Atos International, 20 December 2004). Hal Leonard sells a Rittor Music DVD, Rock Drum Fills, 57 minutes long, on which he demonstrates more than 230 fills in rock, funk, blues and Latin styles, using two live Prism performances to show them in a song. He endorses Pearl drums and Sabian cymbals, and the equipment page on Prism's own site lists a Pearl Carbonply Maple kit and a range of Sabian cymbals, along with the kit used to record Celebrate and What You See in 2017.

Public sources say little else. Neither his Discogs entry nor his Wikipedia article carries a biography beyond these details, he has no recording under his own name, and how he learned the instrument is not documented. His present status is not documented either: Sony's and Sabian's pages describe him as active with Prism and in support of Oda, but neither page is dated.

Kimura's place in the catalogue is that of a fusion drummer who is also a working session player. Discogs files 57 of his 84 officially issued releases under Jazz or the Fusion style, and the Prism albums he plays on are tagged Fusion and Jazz-Rock, and on some Jazz-Funk. Wikidata describes Prism as a Japanese jazz fusion band, and Apple Music files his own artist page and the band's under Jazz. The other 27 officially issued releases are pop, rock, new wave and classical records, mostly Oda's and the idol-pop sessions listed above, so the jazz side is the larger part of the credit list but not the whole of it.

Prism's sound, as Japanese Wikipedia describes it, starts from instrumental hard rock and adds jazz, ethnic and progressive-rock elements, with early reference points in Santana, Return to Forever and Al Di Meola. What Kimura's drumming adds to it shows in the credits more than in any description: percussion on most of the later albums, electronic drums on Nothin' Unusual, drum programming on Uncovered. The Discogs entry for A Personal Change is tagged Prog Rock alongside Fusion, and two of that album's pieces are his. His other compositions for the band include "Spiral Blues" (Whiter, 1997), "Phoenix Island" (In the Last Resort, 2001), and "Lights in the Distance" and "Struggling Blues" (What You See, 2017).

The Hal Leonard DVD covers fills in rock, funk, blues and Latin styles, which are also the idioms of the records he plays on, from the Latin pulse of the Matsuoka albums to the rock-edged fusion of Prism.