T-Square (band)

T-Square (formerly known as The Square), stylized in all-uppercase T-SQUARE, is a Japanese jazz fusion band formed in 1976. They became famous in the late 1970s and early 1980s along with other Japanese jazz bands. They are known for songs such as "Truth", "Japanese Soul Brothers", "Takarajima", "Omens of Love", among others.

During the first years simply The SQUARE was printed on the frontsides of their albums. After the renaming of the band to T-Square the imprint changed to T-SQUARE (all in Capital letters) and their typical logo became a capital letter T printed over a red square. During the years with the changing names of the band the logo got modified several times, reflecting the changing band names such as T-Square alpha (where an α sign got added to the logo ), T-Square plus (where the text "plus" was added centered next to the T in smaller letters ).

"Truth" was used as the theme for Fuji Television's Formula One coverage from 1987 to 1998 and starting in 2012. Special arrangements were used as the theme for Japan's F1 2001 to 2006.

The band has won, all told, 12 Japan Gold Disc Awards. In the 80s, "SPORTS", "Truth", "Yes, No", and even their "F1 Grand Prix" compilation album won Gold Discs in the Jazz-Fusion category. In the 90s, "Natural", "Impressive", "Human", "Natsu no Wakusei", "B.C. A.D." and "Gravity" all won Gold Discs. After more than two decades without Gold Discs, they've recently won back-to-back for 2021's "FLY! FLY! FLY!" and 2022's "WISH" as part of the Instrumental Album of the Year category.

The Square (1976–1988)
In 1976, The Square started as a small jazz fusion group in Meiji University with a very basic line-up, made of bassist Yuhji Nakamura, guitarist Masahiro Andoh, pianist Jun Hakamazuka and drummer Shunichi Harada. According to Masahiro Andoh, the band's name was based on Madison Square Garden. Hakamazuka was replaced by Junko Miyagi on keyboards.

Meanwhile, in the Nihon University of the Arts, saxophonist Takeshi Itoh and Drummer Michael S. Kawai played in a few other college bands together. When those disbanded, Kawai became fast friends with Andoh, replacing Harada on drums within The Square, and Takeshi Itoh made many guest appearances with the band, officially joining on saxophone and flutes, in 1977.

With backing guitarist Yuhji Mikuriya, keyboardist Shiro Sagisu and percussionist Kiyohiko Senba joining in 1978, the band was signed to CBS/Sony and released their first studio album, Lucky Summer Lady. It had a semi-generic, disco-type sound. Lead saxophonist Takeshi Itoh adopted the Lyricon as a side instrument. The Square would then begin a tradition of writing one to three songs with the Lyricon in every new album thereafter. As the years progressed, the number of members had dwindled from eight members (two keyboardists, two guitarists, a drummer, a Percussionist, a sax player and a bassist) to five (a drummer, a keyboardist, a guitarist, a sax player and a bassist). The group's sound had also evolved to a more rock-oriented music when Junko Miyagi was replaced by Prism (ja) keyboardist Daisaku Kume and Michael S. Kawai was replaced by drummer Jun Aoyama (better known as Tatsuro Yamashita's support drummer from 1979 to 2003). The band would also have vocalists, with Rockoon being the first of two albums to prominently feature one. Jun Aoyama was later replaced by Eiji Shimizu on drums and Yuhji Nakamura was replaced by bassist Toyoyuki Tanaka in 1981. Tanaka's slap-bass influenced a tonal shift to the band.

In 1982, Tohru Hasebe replaced Shimizu and Hirotaka Izumi replaced Kume. Izumi eventually became the second longest-tenured keyboardist over 15 years in the band (1982–97). This would be the band's first consistent line-up, lasting until late 1985. Hiroyuki Noritake would then replace Hasebe on drums that same year as their first long-term drummer. By the end of 1986, Mitsuru Sutoh replaced Toyoyuki Tanaka on bass, being the first long-term bassist in the group. Takeshi Itoh would go on to swap his Lyricon – an instrument crafted in the 1970s with not many people to repair it – for a mass-produced Yamaha WX7, which he would further swap out for an EWI instead.

In an attempt to not confuse the Western Audience with a name that sounds too close to "The Squares", "Truth" was released in the United States and Canada through Portrait Records, a sister imprint of Columbia and Epic Records and a subsidiary of Sony Records. While this album's Japanese release still refers to the band as "The Square", Portrait Records' reprint would be the first to refer to them as "T-Square", and included the logo of a T and a Red Square later used in their albums.

Their first performance in the United States was at the Cat Club in New York City in December 1987 and it was released on Laserdisc early 1988, still as "The Square".

T-Square (1988–2000)
Their 1988 album, "Yes, No" was released in Japan only, with no Western Reprint, and thus still referred to them as "The Square", but they performed at the Roxy in Los Angeles on November 3 that same year as "T-Square". This is the first concert to use the now-established T-Square logo onstage. In 1989, they released their first studio album, in no uncertain terms, now as "T-SQUARE", Wave. The band would also appear alongside Ottottrio (with guitarist Hirokuni Korekata) and Casiopea in The Super Fusion that same year. In 1990, saxophonist Masato Honda debuted with them as a backing saxophonist on the album T-Square Live (featuring F-1 Grand Prix Theme). By the end of 1990, Takeshi Itoh left the group to pursue a solo career in the US, and Honda replaced him in 1991. Honda also composed the opening track from T-Square's New-S album, "Megalith". After the release of the Blue in Red album in 1997, Honda left the group to pursue his solo career. Takahiro Miyazaki would replace him. At the same time, Hirotaka Izumi left T-Square and was replaced by Tadashi Namba. Namba played keyboards on the theme song from Gran Turismo, "Moon Over The Castle" (from Masahiro's solo album Andy's, released in 1996 ) as well as the T-Square arrangement of the song, called "Knight's Song", from Blue in Red. The group and all former and (at the time) current members played at Yaon de Asobu (野音であそぶ) for their 20th anniversary that same year. At the end of 1998, Tadashi Namba was replaced by Keiji Matsumoto. The new line-up of Miyazaki, Noritake, Sutoh, Matsumoto and Andoh was kept until the group's brief disbandment in mid-2000.

Unit era (2000–2004)
In mid-2000, the band was divided into T-Square (original and long-term guitarist Masahiro Andoh, returning saxophonist Takeshi Itoh and session musicians) and Trio The Square (bassist Mitsuru Sutoh, drummer Hiroyuki Noritake and keyboardist Keiji Matsumoto). This trio was the main reason for why T-Square had to employ session musicians to record. However, the Friendship Live performance had ex long-term drummer, Hiroyuki Noritake, along with support bassist Kiyoshi Murakami and keyboardist Keizoh Kawano, the latter of whom started in the band as a support member, eventually to become the longest tenured keyboardist over 20 years with T-Square. T-Square used the name T-Square Plus for hard rock arrangements of their songs. Fence of Defense guitarist Kenji Kitajima, former Seikima-II bassist Shunsuke "Xenon" Ishikawa, session keyboardist Takehiro Kawabe, etc. joined them briefly in 2001 and 2002. After that, the band no longer used session musicians.

In 2003, T-Square released the album Spirits under their original name "The Square", and retained some of their original members (partly due to T-Square's 25th anniversary that year ) and kept their newcomer, Keizoh Kawano. The line-up was Itoh, Noritake, Sutoh, Kawano, Izumi and Andoh. They released another album, T Comes Back, that featured new arrangements of some of their best known songs.

Resurrection of the band format (2004–2019)
In 2004, Keizoh Kawano became an official keyboardist, and Katsuji Morioka joined and replaced Mitsuru Sutoh on bass. Only a few months after the release of their album, "Groove Globe", Satoshi Bandoh replaced Hiroyuki Noritake on Drums. In 2005, not long after the release of "Passion Flower", Morioka was replaced by Shingo Tanaka as support bassist, and they continued to turn with this lineup, seen in the "Passion Flower Live" DVD. T-Square's original drummer, Michael S. Kawai, returned as a behind-the-scenes percussionist and producer from 2004 to 2008.

The band used the name T-Square Super Band to promote their 30th anniversary tour. Most former T-Square members were involved in recording their new album, Wonderful Days. After the end of the Wonderful Days tour, the group used the name T-Square Super Special Band to play on Yaon de Asobu for their 30th anniversary show. This show was released in February 2009 as The Square ~ T-Square since 1978: 30th Anniversary Festival. Their 2009 album Discoveries was sold with a DVD which chronicled T-Square performing and rehearsing in 2008.

In 2010, T-Square released a brand new album, Jikan Ryoko (時間旅行). This album was meant to showcase more of the songwriting abilities of the younger members of the group. In the summer of that same year, T-Square rerecorded some of their older songs and released them in October as an album called Takara no Uta (宝曲), with T-Square plays The Square as a subtitle.

T-Square released another album, Nine Stories, in April 2011. Some current and former T-Square members would tour with Satoshi Bandoh to promote his solo album, Happy Life!, in late 2011. T-Square recorded another T-Square plays The Square album, Yume no Uta (夢曲) released in October 2011, much like the year prior. Keizoh Kawano recorded and released his own solo album, Dreams, in November. At the end of 2011, they performed a new song, "Bird of Wonder", which was released with their 2012 album Wings. The group later released another cover album in 2012, Niji no Uta (虹曲), this time employing the help of special guest musicians, such as jazz pianist Yosuke Yamashita.

T-Square branded themselves "T-Square Super Band" for the second time, now in promotion of their 35th anniversary tour. They retained all members of the Super Band from 2008, including percussionist Kiyohiko Senba and excluding pianist Hirotaka Izumi. Upon the release of the album Smile, a picture was included in the release, reading something related to "Itoh's resignation", making fans believe that Takeshi Itoh would once again leave the band. In another album of 2013, History, Itoh only performed on two tracks of the album, but did not leave the band.

T-Square's 35th Anniversary Festival show was released as a Blu-ray in May 2014. Nearly a month later, their album was released, NEXT.

The 40th T-Square album, Paradise, was released in July 2015, being one of ten T-Square albums (along with Lucky Summer Lady, Midnight Lover, Make Me a Star, Magic, Kyakusenbi no Yuuwaku (脚線美の誘惑), Stars and the Moon, S.P.O.R.T.S., Yes, No, and Friendship ) not to be released in the spring. Paradise was the first T-Square album to be released on iTunes and Spotify in the United States, along with their following album from 2016, Treasure Hunter.

In 2017, T-Square performed two separate concerts at Blue Note Tokyo, under the name "The Square Reunion". The first one included their 1982–1985 lineup of Masahiro Andoh, Takeshi Itoh, Tohru Hasebe, Toyoyouki Tanaka, and Hirotaka Izumi with Keizoh Kawano playing backing synth; the second one included their 1987–1990 lineup of Masahiro Andoh, Takeshi Itoh, Hiroyuki Noritake, Mitsuru Sutoh, and Hirotaka Izumi with Keizoh Kawano playing backing synth. T-Square released the album REBIRTH on April 26.

In 2018, T-Square released two albums, City Coaster in April and It's a Wonderful Life! in November. "It's a Wonderful Life!" was also the name of their 40th anniversary concert. This particular concert included most of their past members, e.g. Daisaku Kume, who hadn't played with T-Square since their 20th anniversary in 1998. This concert also included a special guest appearance of the Nishiarai Junior High School Brass Band Club, who performed "Takarajima".

T-Square Alpha (2019–2023)
T-Square had planned to record their next album Horizon in Los Angeles, but on February 6, 2019, their keyboardist Keizoh Kawano was hospitalized due to an intracerebral hemorrhage which paralyzed the left side of his body. Due to the abrupt changes, the T-Square members were not free to travel to the U.S. to stay and record the album, so Philippe Saisse, who hadn't played with T-Square since the T-Square and Friends album Miss You In New York from 1995, but played on Satoshi Bandoh's album Step By Step from 2016, offered to finish the keyboard parts. They managed to release Horizon in April 2019. The new formation, with Saisse replacing Kawano temporarily, was then called T-Square Alpha, indicating the name change also by adding an alpha sign to their logo, and they used this name while touring to promote Horizon in concerts.

T-Square scouted Akito Shirai as a session keyboardist. With both Shirai and Kawano providing synthesizer parts, the band recorded and released AI Factory to a two-month delay as a result of the COVID-19 pandemic. On October 28, 2020, T-Square released a new self-cover album titled Crème de la Crème, part of which includes a hand-picked collection of Keizoh Kawano's best songs. This was T-Square's last album within Kawano, who would continue activities such as working as a composer.

At some point during the end of 2020, T-Square's albums released prior to 2015 became available to all streaming services.

On February 1, 2021, Masahiro Andoh announced that he would leave T-Square after releasing their upcoming album (not yet named at the time) and completing their 2021 tour, wishing to continue activities as a solo guitarist. At the same time, after Masahiro Andoh's departure, Takeshi Itoh and Satoshi Bandoh announced they would form T-Square Alpha, and months later, it was announced that guitarist Yuma Hara would take Andoh's spot. T-Square released the album ''FLY! FLY! FLY!'' in April 2021, which was awarded the Golden Disc Award 2022 for the instrumental album of the year by the Recording Industry Association of Japan (RIAJ).

On April 26, 2021, Hirotaka Izumi died suddenly due to acute heart failure. Accordingly, T-Square performed concerts of mostly Izumi-penned T-Square songs that month. They would continue to hold Izumi memorial concerts yearly since 2022.

The day after the release of the special edition of Crème de la Crème in July 2021, T-Square toured to honor Masahiro Andoh's farewell in concerts. Days after their participation in Sapporo City Jazz, T-Square's 2021 year-end shows saw the first performance by Keiji Matsumoto since 2000.

On May 18, 2022, T-Square's 49th Album, WISH was released. This album marked the first time in close to 25 years that Masato Honda and Keiji Matsumoto recorded Studio Parts with T-Square. This album was also awarded the RIAJ's Golden Disc Award 2023 for Best Instrumental Album.

Masato Honda and Takahiro Miyazaki performed together in September 2022. With T-Square's "Year End" Shows in December 2022, Masato Honda performed with the T-Square Alpha Lineup, herein referred to as T-Square Alpha X. This new formation indicated the name change also with the letter X coming from words "Double Sax", and they used this name to promote their 45th anniversary tour.

On January 18, 2023, T-Square released a digital album of their Live Concert from December 31, 2021, and, on March 1, 2023, a digital album of their Concert Tour from July 3, 2022.

45th anniversary and onward (2023–present)
Their 50th album VENTO DE FELICIDADE was released on May 31, 2023. This release was commemorated with two concerts at Blue Note Tokyo in June.

The T-Square Alpha X Lineup performed on a Blue Note Tokyo special event titled Jazz Fusion Summit 2023 on July 17.

T-Square held their 45th Anniversary Concert on October 21, 2023, in the Tokyo International Forum Hall A. This particular concert included the Nishiarai Junior High School Brass Band Club, Kazumi Watanabe, Yuji Toriyama, and the Masato Honda Big Band Station as special guest performers.

Later that same night, in an attempt to prolong the activities of the band, the T-Square Fans and Staff Facebook Page made a post announcing that, in order to create more music and potentially celebrate a 50th Anniversary and beyond, they were opening Online Auditions, seeking new band members and/or composers. The Deadline was December 31, 2023. This audition will be commemorated with two concerts at the Cotton Club in Tokyo in August 2024.

T-Square's 2023 year-end shows saw three saxophonists perform together like the previous year.

The Square Reunion lineup will perform on the first day of Hiroyuki Noritake's 60th birthday concerts in September 2024.

Video game influence
T-Square's music, as well as the jazz fusion genre as a whole, would heavily influence early video game music. Most notably, video game composer Koji Kondo would take inspiration from the 1984 T-Square song "Sister Marian" when composing the main theme for the 1985 platformer game Super Mario Bros. Many other video game series would later be rumored to have taken inspiration from T-Square music, including Street Fighter, Sonic the Hedgehog, and more. Members of T-Square have also worked on video game music directly.

Members

 * Takeshi Itoh – saxophones, EWI (1977–1990, 2000–present)
 * Satoshi Bandoh – drums (2004–present)

Support members

 * Shingo Tanaka – basses (2005–present)
 * Audition guitarist (2024)
 * Audition keyboardist (2024)

Saxophone
All of the following saxophonists also played flute and EWI during their Tenure with T-Square.


 * Takeshi Itoh (1977–1990, 2000–present)
 * The original saxophonist and second longest-running member of T-Square overall. He left the group at the end of 1990 to pursue his solo career and returned to the group in late 2000, starting with the album Friendship. As Masahiro Andoh resigned from T-Square in 2021, Itoh is essentially the Bandleader.
 * Masato Honda (1991–1997 as Full-Time member; 2022–present as Support Member)
 * The second saxophonist of T-Square. He first recorded with the band in 1990 and was welcomed in the original Farewell & Welcome concert in early 1991, replacing Takeshi Itoh. He is best known for songs like Megalith, Little League Star, Traffic Jam, Summer Mirage (夏の蜃気楼), Bad Moon, Samurai Metropolis, etc. He left T-Square after the release of Blue in Red in 1997 to begin his solo career as well, having only attended their 20th Anniversary Concert in 1998. After leaving, he would work with musicians such as bassist Tomohito Aoki, trumpeter Eric Miyashiro, guitarist Jun Kajiwara, etc., and form Voice of Elements with former T-Square members Keiji Matsumoto, Mitsuru Sutoh, and Hiroyuki Noritake. Masato contributed brass arrangements and recorded Saxophone parts (and even recorded trading solos with his predecessor, Itoh, on the title track, "As You Wish") for T-Square's 2022 Album, "WISH", 24 years after leaving the band. Honda returned as a member of the newly renamed T-Square Alpha X after a run of "Welcome Back" concerts in December 2022. Consequently, he would appear on T-Square's 50th Studio Album, Vento de Felicidade and the 45th anniversary concert that would come soon after.
 * Due to his capabilities as a Multi-Instrumentalist, the studio recordings of Human and Welcome to the Rose Garden had the brass section being all played by himself. This was emphasized in many live performances, in which he was credited simply as playing "Brass Instruments". This concept was taken even further when Masato released and produced his second solo album, "Carry Out", entirely on his own. On this album, Honda played Woodwind and Brass Instruments, as usual, but he additionally programmed Synthesizers, played Piano, Guitar, Bass, Drums and provided vocals.
 * Takahiro Miyazaki (ja) (1998–2000)
 * The band's third, and shortest-tenured full-time saxophonist, being welcomed alongside Tadashi Namba in the second Farewell & Welcome concert in 1998 as one of the replacements of Masato Honda and keyboardist Hirotaka Izumi. He appeared as the sole leading saxophonist in the studio album Gravity in 1998, Sweet & Gentle in 1999, and finally, their self-titled album T-SQUARE in early 2000. However, the album Vocal2 in 2002 was his first recording with the band since his departure. Furthermore, he continued to appear in all anniversary concerts since the 20th anniversary special (being the first overall) in 1998.

All 3 Saxophonists worked together for one album, Four Nine.

Guitar

 * Masahiro Andoh (ja) (1976–2021)
 * The founding guitarist, main composer and leader of T-Square. He is one of three guitarists (alongside Casiopea guitarist Issei Noro and guitarist Hirokuni Korekata) in the supergroup Ottottrio and has also been well known for songs such as "Moon Over the Castle" in the Gran Turismo series. Briefly disbanded the group shortly after the tour promoting their self-titled album in 2000, as he initially left the band and wanted to find a new guitarist to continue the band's activities, but returned with saxophonist Takeshi Itoh later that year. He left the band in 2021 after the end of the tour honoring his farewell.
 * Yuhji Mikuriya (1978–1979)
 * Appeared in the band's debut albums Lucky Summer Lady and  Midnight Lover in 1978. He also formed a guitar duo with Masahiro Andoh called anmi2. His role is more of a Rhythm Guitarist, in contrast to Andoh playing lead.
 * Yuma Hara (2021–2023, Support Member)
 * A guitarist with only 2 solo studio albums to his name, but also an Arranger for several J-Pop artists, that began performing with T-Square alpha on concerts at Blue Note Tokyo in October 2021. His first album alongside T-Square was their 2022 album "Wish".
 * Kazuma Sotozono (ja) (2022–present, Support Member)
 * Began recording on T-Square's 2022 album "Wish", accompanied the band as a support member at a number of their Year End Live shows of that year, and continued to perform with the group since, including recording on their 45th Anniversary album "Vento De Felicidade" and performing at Blue Note Tokyo's Jazz Fusion Summit in July 2023.

Keyboards

 * Jun Hakamazuka (ja) (1976–1977)
 * The band's pianist during the formation. He left the group and became a professional jazz pianist.
 * Junko Miyagi (ja) (1978–1979)
 * Replaced Jun Hakamazuka on keyboards in 1977 and has also worked in the band's first three studio albums, also leaving in 1979. Her role was briefly filled by keyboardist and songwriter Izumi Kobayashi in mid-1979 only.
 * Shiro Sagisu (1978)
 * Was a Support Keyboardist in The Square's first studio albums. He left between early and mid-1979 and went on to write 2,000-plus Songs, TV/Advertisement Jingles and Incidental Music for Films and Anime series, most notably, Kimagure Orange Road and Neon Genesis Evangelion.
 * Daisaku Kume (ja) (1979–1981)
 * Was part of Prism before joining The Square at the end of 1979. His first studio appearance was in 1980. He left in 1982, but would appear in the 20th, 40th, and 45th Anniversary concerts.
 * Hirotaka Izumi (ja) (1982–1997 as Full Member; 2003 and onward as Occasional Support-Member) (died April 26, 2021)
 * Replaced Daisaku Kume and joined at the same time as Tohru Hasebe. He was the first long-term keyboardist of the band. He composed songs with examples consisting of Omens of Love, Forgotten Saga, Takarajima, Cape Light, Cry for the Moon, Twilight in Upper West, etc. He officially departed from the band in 1997, but he would sometimes be called in as a guest musician for T-Square Anniversary/Classic Lineup Reunion concerts for the 2000s and 2010s until his death due to acute heart failure on April 26, 2021. Two of his songs, Omens of Love and Takarajima were rearranged into orchestra version by Toshio Mashima and became famous as the standard songs for many brass bands in Japan.
 * In addition to playing Piano, Izumi originally handled Auxiliary Synthesizer work (Brass Parts, String Parts, sometimes even going as far as to actually help write parts for Brass and String Sections in the Studio Version of their songs), but since 1997, expressed a want to simply play piano.
 * T-Square has hosted concerts in an annual cycle (since 2022) with the setlist mainly consisting of Izumi songs as a show of respect for his tenure in the band, punctuated by his Classically inclined, Jazz & Pop-friendly style of songwriting that has become a trademark of not only his own sound but that of The Square in the 1980s and 90s.
 * Tadashi Namba (ja) (1998)
 * Joined the band to fill the keyboardist role in 1998 after Hirotaka Izumi left. He would only record in Gravity, and would perform in Farewell & Welcome Live 1998 and the 20th anniversary reunion. He left T-Square a few months later.
 * Keiji Matsumoto (ja) (1998–1999, 2021–present as "Special Support"; 1999–2000)
 * Replaced Tadashi Namba and joined T-Square at the end of 1998 as a support member. He became an official member of T-Square after the release of Sweet & Gentle in 1999. He left the group after its dissolution to work as a session pianist. Notably, he has recorded and performed with the likes of Masato Honda, Masayoshi Takanaka and The Super Mario Players. In December 2021, Matsumoto made a full return to T-Square as a support member, marking his first activities with the band since the album Vocal2 in 2002.
 * Keizoh Kawano (2000–2004, 2020–present (as "Special Support"); 2004–2020)
 * The longest-tenured keyboardist of T-Square (with 4 years as a Support Member and 16 years as an official keyboardist), joining in late 2000 as a support keyboardist. His first documented appearance with T-Square is in their "Friendship Live" concert video. Kawano's predecessor, Hirotaka Izumi, would sometimes play grand piano as a guest in T-Square concerts, while Kawano would perform Auxiliary Synth work. Kawano became the main keyboardist of T-Square in 2004, a role he held for 15 years until he became hospitalized with a stroke in 2019, leaving him unable to use the left side of his body. His role was filled by keyboardist Philippe Saisse, Yudai Satoh, and Akito Shirai. Crème de la Crème was his last album with T-Square as an official member. However, he intends to continue activities like contributing to some of the compositions for T-Square's future music.
 * Philippe Saisse (1995, 2019, Support Member)
 * Performed on the T-Square and Friends album "Miss You In New York" in 1995 and T-Square drummer Satoshi Bandoh's album "Step By Step!" in 2016. He would temporarily replace Keizoh Kawano during the Tour supporting their 2019 Album "Horizon".
 * Akito Shirai (2019–present, Support Member)
 * Joined during their 2019 tour in Seoul. His first album with the group was A.I. Factory in 2020.
 * Yudai Satoh (ja) (2019–2022, Support Member)
 * Before performing with T-Square itself, he performed with Hirotaka Izumi, Kiyoshi Murakami and Masami Itagaki in 2008, for Izumi's "Live 0801" Concert Video. Little more than a decade later, he performed on their Live Tour to promote their 2019 Album "Horizon". He also appeared in one of Masahiro Andoh's "Farewell Tour" performances alongside T-Square, with his first Studio Recording in T-Square being 2022's "WISH".

Bass

 * Yuhji Nakamura (1976–1980)
 * The Square's original bassist. He appeared in the first four albums and was replaced by Toyoyuki Tanaka in 1981.
 * Toyoyuki Tanaka (ja) (1981–1986)
 * Replaced Yuhji Nakamura and first appeared in the studio album Magic, adding slap-bass to give the band a more rock and funk sound, as well as composing songs such as Rodan, Between, Stingray, Stimulator, and Overhead Kick. He left the band after the end of the S.P.O.R.T.S. tour in 1986.
 * Mitsuru Sutoh (ja) (1986–2000 as Full Member; 2003 and onward as an Occasional Support Member)
 * The first long-term bassist of T-Square. He joined the group at the end of 1986 and debuted in one of their most famous albums, Truth in 1987. He composed songs such as "Nab That Chap", "Dooba Wooba" (alongside Hiroyuki Noritake), "Sunnyside Cruise", "Pioggia Di Capri", "From the Bottom of My Heart", "Explorer", "Ms. Bracing", "Scrambling", "Our Fortress", and "An Evening Glow". He left after the group disbanded in 2000, and returned for the band's 25th anniversary in 2003 with Hirotaka Izumi. He also formed the band TRIX alongside former Casiopea drummer Noriaki Kumagai.
 * Kiyoshi Murakami (ja) (2000, Support Member)
 * One of the session bassists during the unit era. He appeared in the live performances in 2000.
 * Shunsuke "Xenon" Ishigawa (ja) (2001–2002)
 * Joined the band as a session bassist of the "Japan version" during their live performances in 2001.
 * Katsuji Morioka (ja) (2004–2005)
 * Appeared in the studio albums Groove Globe in 2004 and Passion Flower in 2005. He also appeared in the Year-End performance in 2003 and their crossover performance with other Fusion band DIMENSION in 2004.
 * Shingo Tanaka (2005–present, Support Member)
 * Debuted with T-Square during their live performance of the album Passion Flower in 2005 as a "Special Support" member. He is the band's second long-term bassist.
 * Sohta Morimitsu (2021–2022, Support Member)
 * Worked on albums Fly! Fly! Fly! in 2021 and Wish in 2022.

Drums

 * Shunichi Harada (ja) (1976)
 * Played during The Square's earliest stages. He left the band shortly after to work in other jazz-related groups.
 * Michael S. Kawai (ja) (1977–1979)
 * Replaced Shunichi Harada, appeared in the band's first three studio albums,  and returned as a guest percussionist in Groove Globe, Passion Flower, Blood Music, and Wonderful Days.
 * Jun Aoyama (ja) (1979–1980) (died December 3, 2013)
 * Replaced Michael Kawai and joined at the end of 1979, appearing in the album Rockoon released in 1980. He was best known as Tatsuro Yamashita's support drummer from 1979 to 2003. He was also in another band after leaving The Square, known as Prism.
 * Eiji Shimizu (1981)
 * Replaced Aoyama on Drums and joined the band alongside bassist Toyoyuki Tanaka in 1981, appearing in the album Magic. He would leave the band with keyboardist Daisaku Kume in mid-1982.
 * Tohru Hasebe (ja) (1982–1985)
 * Before joining The Square in 1982, he was in ANKH that formed in 1980. His first appearance with The Square was in the album Temptation of Shapely Legs. He left The Square in late 1985, but is one of many past members who have appeared in multiple reunion concerts.
 * Hiroyuki Noritake (ja) (1985–2000 as Full Member; 2000–2004 and after as Occasional Support)
 * Replaced Tohru Hasebe on Drums at the end of 1985. He is T-Square's second longest-tenured drummer (for 15 years as an official member and, subsequently, as a Support Member for 4), also being a co-composer of the track Dooba Wooba! from the album Wave in 1989, with his first individual composition of the band being No More Tears from Natsu no Wakusei (夏の惑星) in 1994. He has also composed tracks such as One Step Beyond, Yuh-Ja, Tooi Taiko, Eurostar etc. He became a "Special Support" member during the band's return in late 2000. He would leave T-Square in mid-2004 after nearly 20 years with the band. Following the Casiopea vs. The Square concert in 2003, he also formed a drummer duo with Casiopea drummer Akira Jimbo in 2004 known as Synchronized DNA (which would also collaborate with Casiopea that same year ).
 * Satoshi Bandoh (ja) (2004–present)
 * T-Square's current and longest-tenured drummer (with 20 years as an official member), joining in the summer of 2004. Aside from T-Square, he has maintained a solo career with 3 albums to his name, he has appeared as a Support drummer for Dimension albums, and has also contributed to some famous video game soundtracks such as Mario Kart 8 and the Gran Turismo series. Due to his busy schedule, his role was filled by Maoki Yamamoto and Senri Kawaguchi.

Percussion

 * Kiyohiko Senba (ja) (1978–1980)
 * The Square's original percussionist. He was an official member since the group's debut up to Rockoon in 1980. However, he would continue to work in most future albums as a guest musician.

The Square Reunion/T-Square Family
In order to differentiate from the Current/Ongoing group known as T-Square (who are officially just Itoh and Bandoh as of 2022), Since September 2000 (beginning, specifically, with the Live Album "Moment – Memorial Live at Chicken George"), the band has occasionally held throwback concerts, going under their old name of The Square (with the word Reunion added in 2017), with their Classic Lineups from the 80s and 90s, performing almost-exclusively their songs from that era. Most-recently, this idea has expanded to where other members, who joined and left after 1989, appear as part of these concerts. Thus, the name "T-Square Family" refers to any random lineup of those who were formerly officially in the band, or were at the very least support members, and are appearing for one-off concerts.

AnMi2/AnMitsuru
AnMi2, named after Anmitsu, are a guitar duo comprising the first two guitarists of T-Square, Masahiro Andoh and Yuhji Mikuriya. For their 10th anniversary, the duo performed with fellow ex-T-Square Bassist Mitsuru Sutoh and was renamed "AnMitsuru".

Trio The Square/The Masato Honda Band/Voice of Elements
This trio first appeared in the T-Square albums Sweet & Gentle in 1999 and T-SQUARE in 2000 with keyboardist Keiji Matsumoto, drummer Hiroyuki Noritake and bassist Mitsuru Sutoh as Trio The Square. They became a standalone group around the time Andoh initially left T-Square, resulting in the dissolution of the band form. Trio The Square disbanded in later 2000.

Later on that year, Hiroyuki Noritake and Keiji Matsumoto, along with bassist Tomohito Aoki and guitarist Jun Kajiwara, would become the backing band of former T-Square saxophonist, Masato Honda. The group didn't have an official name, but it was collectively dubbed by fans as "The Masato Honda Band".

The backing band was put on hold in 2005, then fully deactivated in early mid-2006 to make way for Voice of Elements, which also featured T-Square alumni Hiroyuki Noritake, Mitsuru Sutoh and Keiji Matsumoto. Tomohito Aoki, the original bassist of the Masato Honda Band, died of acute heart failure in June that year, and was replaced by Sutoh for following Masato Honda Band activities. Voice of Elements, as the band was called when they returned in 2006, continued performing occasionally between 2007 and 2020. Both Keiji Matsumoto and Masato Honda are credited as guest performers on the 2022 T-Square album, "WISH", while both Hiroyuki Noritake and Mitsuru Sutoh are credited as guest performers on the 2023 T-Square album, "Vento de Felicidade" alongside Matsumoto and Honda.

Ottottrio
This group was a fusion supergroup led by 3 guitarists: T-Square's Masahiro Andoh, Casiopea's Issei Noro and Rocket Jam's Hirokuni Korekata. Along with Masahiro Andoh, Drummer Hiroyuki Noritake was another T-Square musician who was part of this group since 1988. Also, T-Square bassist Mitsuru Sutoh (who would leave T-Square in their brief disbandment two years later) and keyboardist Keiji Matsumoto (who would join T-Square a few months later) recorded with them at the end of 1998. Noro and Korekata appeared in T-Square's 35th Anniversary concert in 2013.

KoreNoS/Rocket Jam
Stylized as KoreNoS, this band was formed in 1998 by Hirokuni Korekata, Hiroyuki Noritake and Mitsuru Sutoh. They released two studio albums, "Asian Street Style" (2004) and "Abracadabra" (2005). They also released a live album in 2007. Hirokuni Korekata also created a new band named Rocket Jam with bassist Shingo Tanaka and drummer Satoshi Bandoh in 2013.

Casiopea vs. The Square
Although "Casiopea vs. The Square" was performed as a one-off event in 2003 (the DVD and the CD have different audio sources, suggesting that there may have been 2 shows ), this extension of 2 different jazz fusion bands goes back to 1989. All members of T-Square, Casiopea, and Ottottrio played in The Super Fusion in 1989 and Kiyohiko Senba, former percussionist of The Square, played on one of the songs from Casiopea's 1993 album, "Dramatic". A year later, both groups played an arrangement of The Beatles' "Get Back" on a Japanese Broadcast. 3 years after that, Casiopea, T-Square and Jimsaku played at Tokyo Jam 1997, with the same song. In 2003, both groups played (with some of the players replaced) at the event called Casiopea vs. The Square. Both groups still have somewhat of an alliance, seeing as Casiopea's 1993 – 1997 drummer, Noriaki Kumagai and former T-Square bassist, Mitsuru Sutoh are both in TRIX. And Sax player Takeshi Itoh performed with Casiopea's Keyboardist, Minoru Mukaiya in 2006.

Synchronized DNA
Drummers Hiroyuki Noritake of T-Square and Akira Jimbo of Casiopea formed a duo in 2003, after the "Casiopea vs. The Square" concert. They were later featured in Casiopea's 2005 album Signal, the aforementioned band's last album before their hiatus the year after.

Pyramid
A group that features pianist Hirotaka Izumi (who would die in 2021), drummer Akira Jimbo and guitarist Yuji Toriyama, along with other studio musicians. They have released four studio albums and one digital album.

Akasaka Trio
Guitarist Masahiro Andoh, Drummer Hiroyuki Noritake and Bassist Mitsuru Sutoh, all former T-Square members from Classic Lineups of the mid-80s to 2000, formed the Akasaka Trio in 2022, following Andoh's exit from T-Square.

As support members for other artists
After the dissolution of Trio the Square, Mitsuru Sutoh and Keiji Matsumoto would later become backing musicians for Japanese a cappella pop group, 'The Gospellers'. Sutoh also plays for TRIX (since that band's formation in 2004), led by Noriaki Kumagai (Casiopea drummer from 1993 – 1996).

Drummer Hiroyuki Noritake, keyboardist Keizoh Kawano, and bassist Ko Shimizu (from Naniwa Express) would record as support members for Japanese fusion/rock guitarist Kumi Adachi in 2007–2008.

T-Square's current bassist Shingo Tanaka is a former part of The 39's/The Thank You's (39 in Japanese can be pronounced as san kyū, which resembles Thank You). The 39's were a band that accompanied concerts performed by Vocaloids, specifically the "39's Giving Day" concert series (it being another pun, this time on "Thanksgiving Day"), although the concerts themselves wouldn't necessarily be held on said day. During the final 39's Giving Day Concert in March 2012, the band were also accompanied by Takahiro Miyazaki.

Discography
Sources:

Original albums

 * Lucky Summer Lady (1978)
 * Midnight Lover (1978)
 * Make Me A Star (1979)
 * Rockoon (1980)
 * Magic (1981)
 * Temptation of Shapely Legs (脚線美の誘惑) (1982)
 * First Album with Hirotaka Izumi on keyboards.
 * The Water of the Rainbow (うち水にRainbow) (1983)
 * Adventures (1984)
 * Stars and the Moon (1984)
 * R.E.S.O.R.T. (1985)
 * Final Album with Tohru Hasebe on Drums
 * S.P.O.R.T.S. (1986)
 * First Album with Hiroyuki Noritake on Drums
 * Final Album with Toyoyuki Tanaka on Bass
 * First Album to win a Japan Gold Disc Award.
 * Truth (1987)
 * First Album with Mitsuru Sutoh on Bass
 * Yes, No (1988)
 * Wave (1989)
 * Natural (1990)
 * The Final Album with Takeshi Itoh as Leading Saxophonist, at least at the time.
 * New-S (1991)
 * The First Album with Masato Honda as Leading Saxophonist
 * Impressive (1992)
 * Human (1993)
 * Summer Planet (夏の惑星) (1994)
 * Welcome to the Rose Garden (1995)
 * B.C.A.D. (1996)
 * Blue in Red (1997)
 * The Final Album with Masato Honda as Leading Saxophonist
 * Final Album with Hirotaka Izumi on keyboards
 * Gravity (1998)
 * The First Album with Takahiro Miyazaki as Leading Saxophonist
 * Only album with Tadashi Namba on Keyboards.
 * Sweet and Gentle (1999)
 * First Album with Keiji Matsumoto on Keyboards.
 * T-Square (2000)
 * The Cover Art of this album is a Brick Wall, setting the tone for a possible break-up to this band.
 * The Final Album with Takahiro Miyazaki as Leading Saxophonist.
 * Trio The Square was formed after this album. The trio was composed of Mitsuru Sutoh, Hiroyuki Noritake and Keiji Matsumoto.
 * Masahiro Andoh, the band's only member who hadn't left his role since 1976, believed the band has reached its limit and couldn't go much farther. He composed more music which became the next album.
 * Friendship (2000)
 * Takeshi Itoh returns as Leading Saxophonist for the first time since 1990. At this point, only he and Andoh are considered T-Square members, and much of the album consists of overseas musicians as Session Players.
 * Brasil (2001)
 * New Road, Old Way (2002)
 * Spirits (2003) (as The Square)
 * For a brief moment, Andoh and Itoh are joined by their 1987–97 Rhythm Section, Drummer Hiroyuki Noritake, Bassist Mitsuru Sutoh and Hirotaka Izumi, though Izumi now strictly plays piano, and newcomer Keizoh Kawano adds auxiliary synthesizers.
 * Groove Globe (2004)
 * Final Album with Hiroyuki Noritake on Drums
 * First Album to include Keizoh Kawano as a Full-Time Keyboardist.
 * Passion Flower (2005)
 * First Album with Satoshi Bandoh on Drums.
 * Blood Music (2006)
 * 33 (2007)
 * Wonderful Days (2008) (as T-Square Super Band)
 * For their 30th Anniversary, T-Square worked with a Lineup of their 80s/90s Musicians, so Shingo Tanaka is absent from recordings/tour.
 * Discoveries (2009)
 * Shingo Tanaka returns for session work.
 * Time Travel (時間旅行) (2010)
 * Nine Stories (2011)
 * Wings (2012)
 * Smile (2013) (as T-Square Super Band)
 * NEXT (2014)
 * Paradise (2015)
 * Treasure Hunter (2016)
 * REBIRTH (2017)
 * CITY COASTER (2018)
 * It's a Wonderful Life (2018) (as T-Square and The Square Reunion)
 * HORIZON (2019)
 * AI Factory (2020)
 * Final Album with Keizoh Kawano on Keyboards
 * FLY! FLY! FLY! (2021)
 * Final Album with Masahiro Andoh, the longest-Tenured T-Square guitarist since 1976.
 * WISH (2022)
 * First Album to include Masato Honda in 24 Years.
 * First Album to include Keiji Matsumoto in 22 Years.
 * For the first time since 2004, T-Square officially only has two members, Takeshi Itoh and Satoshi Bandoh.
 * VENTO DE FELICIDADE (しあわせの風) (2023)

Collaboration albums

 * F-1 Grand Prix World (1992)
 * SOLITUDE – Dedicated to Senna (1994) (as T-Square and Friends)

Live albums

 * The Square Live (Vinyl/CD) (1985)
 * This was recorded from June 21–24, 1985, while a separate video under the same name was recorded shortly after on July 2.
 * T-Square Live – Featuring F-1 Grand Prix Theme (1990)
 * Although this is Masato Honda's first appearance with T-Square, he isn't considered yet a Leading Saxophonist.
 * T-Square Live – Farewell & Welcome (1991)
 * Yaon de Asobu – 20th Anniversary Special (1998)
 * Technically, not an album, but a concert that aired on Japanese Cable Channel Viewsic in July 1998.
 * Moment (2001)
 * Casiopea vs. The Square Live (2004)
 * Year End Live 20151219-24 Best Take Complete Selection (2016)
 * Year End Special 2021 at Nihonbashi Mitsui Hall (2023)
 * Hall Concert Tour 2022 "Wish" at Namba Hatch (2023)

Rearrange albums

 * Natural (U.S. Version) (1990)
 * Refreshest (1991) (as T-Square and Friends)
 * Classics (1992) (with Royal Philharmonic Orchestra)
 * Harmony (1993) (with Royal Philharmonic Orchestra)
 * Takarajima (1995) (with Munich Symphony Orchestra and City of London Wind Ensemble)
 * Miss you in New York (1995) (as T-Square and Friends)
 * Truth 21 Century (2001) (as T-Square Plus)
 * Vocal2 (or Vocal Square) (2002) (as T-Square and Friends)
 * First Album to include Keizoh Kawano on a few select tracks playing auxiliary synths.
 * T Comes Back (2003)
 * History (2013) (as T-Square Plus)

Self-cover albums

 * Treasure Songs – T-Square plays The Square (2010)
 * Dream Songs – T-Square plays The Square (2011)
 * Rainbow Songs – T-Square plays T- and The Square Special (2012)
 * Crème de la Crème (2020)

Unofficial singles

 * Japanese Soul Brothers (1979) (NHK broadcast)
 * The first official recording of this song that isn't from a Radio or TV Broadcast, was in their 1985 Live Album.
 * The first official Studio recording of this song is from their 1998 Album, "Gravity", as a Bonus Track, thanking the fans for supporting T-Square for 20 years.
 * Jungle Strut (1982)

Compilations

 * Light Up (1983)
 * The Best Of The Square (1983)
 * All About Us (1984)
 * Color Palette (1987) (as The Square and Friends)
 * F-1 Grand Prix (1989)
 * Megalith (1992)
 * Exciting Peace (1998)
 * Wordless Anthology I (1999)
 * Wordless Anthology II (1999)
 * Wordless Anthology III (1999)
 * Single Collection (2001)
 * 25th Anniversary (2004)
 * Wordless Anthology IV (2006)
 * Wordless Anthology V (2006)
 * The Box (2008)
 * 35th Anniversary The Box More (2013)
 * 35th Anniversary The Box 2013 (2013)
 * Dolphin Through (2015)
 * Crème de la Crème – Édition spéciale (2021)

Videography

 * Concert Live Adventures (1984)
 * R.E.S.O.R.T. (1985)
 * The Square Live (VHS/LaserDisc) (1985)
 * Truth (CDV) (1987)
 * Live in New York (1988)
 * Live At Roxy (1989)
 * Live "Natural" (1990)
 * Truth 1991 Version (1991)
 * Megalith (1991)
 * Club Circuit Human '93 (1993)
 * Harmony (1994)
 * T-Square and Friends Live In Tokyo (1995)
 * Farewell & Welcome Live 1998 (1998)
 * Friendship Live (2001)
 * Casiopea vs. The Square – The Live (2004)
 * Live Passion Flower (2005)
 * Visual Anthology Vol. 1 (2005)
 * Visual Anthology Vol. 2 (2005)
 * Visual Anthology Vol. 3 (2005)
 * Concert Tour 2008 Final Wonderful Days (as T-Square Super Band) (2008)
 * 30th Anniversary Festival (2009) (as T-Square Super Special Band)
 * 35th Anniversary Festival (filmed in 2013, released 2014 ) (as T-Square Super Special Band)
 * Fantastic Square Live (2015)
 * Concert Tour "Treasure Hunter" (2016)
 * The Legend – The Square at Yokohama Live for the first time in 31 years (2016)
 * "The Legend" / The Square Reunion Live at Blue Note Tokyo (2017)
 * "Fantastic History" / The Square Reunion Live at Blue Note Tokyo (2017)
 * 40th Anniversary Celebration Concert "It's A Wonderful Life" Complete Edition (2018) (as T-Square Super Band Special and Nishiarai Junior High School Brass Band Club)
 * Horizon Special Tour at Blue Note Tokyo (2020)
 * 2020 Live Streaming Concert at Zepp Tokyo (2020)
 * Masahiro Ando Farewell Tour (2021)
 * Concert Tour "Fly! Fly! Fly!" (2021)
 * In Memoriam Hirotaka Izumi (2022)
 * Welcome Back, Masato Honda! (2023)
 * 45th Anniversary Celebration Concert (2024)