Tetsu Saitoh (齋藤徹) was a Tokyo-born double bassist, composer and bandleader who spent four decades moving between free improvisation, Argentine tango, Brazilian choro, Korean shamanic music and Japanese traditional instruments, and who served as a frequent bridge between the Japanese improvised-music scene and its European counterpart. He was born on October 27, 1955, and passed away on May 18, 2019, after a long battle with cancer.

He came to the instrument late. He began playing the bass at 22, taught himself at first, and then studied with Keizo Mizoiri, a former high school classmate, and with Nobuyoshi Ino, to whom Mizoiri introduced him. By day he practiced at Gaya, an art gallery and live music club in his neighborhood. The owner liked what he heard and put him on stage in the evenings, and so Saitoh began playing free jazz in front of an audience about twice a month, alongside the alto saxophonist Kazutoki Umezu, the pianists Yoriyuki Harada and Katsuyuki Itakura, and the baritone saxophonist Shoji Ukaji. In the early 1980s he was also a member of Kuchu Sampo (Walk in the Cosmos), a collective of artists, musicians and dancers.

Gaya closed in 1984. According to his own biography, Saitoh then spent six months in the group of the percussionist Masahiko Togashi before moving to the group led by the guitarist Masayuki Takayanagi. One tape of that period survives: on December 8, 1985, at Aketa no Mise in Tokyo, Takayanagi was recorded live with Ino and Saitoh as his two bassists, and the set was issued in 2025 as Holy Holy by Takayanagi's Angry Waves. On May 7, 1986, at Vario Hall at the Shobi College of Music in Tokyo, he recorded his first album, the unaccompanied Tokio Tango. Two lasting commitments began the same year. On the advice of the cellist Keiki Midorikawa he started playing tango, joining a tango orchestra as bassist and arranger, and he had the chance to play with Osvaldo Pugliese when the orchestra performed in Buenos Aires. He also became musical director of the theater group TAO, a post he held for every one of its productions through at least 1996. In 1989 he formed a group to play the music of Astor Piazzolla, recorded as Tetsu Plays Piazzolla at Kuchu Sampo Kan in Yugawara in February 1990.

The next few years show how wide his range had become. In December 1988 he recorded Coloring Heaven with Barre Phillips, the American bassist who became one of his most frequent partners, plus the drummer Sabu Toyozumi and the 17-string koto player Hideaki Kuribayashi; Phillips sits in the right channel and Saitoh in the left. He toured North America in 1988 with a free jazz trio of himself, Ukaji and Toyozumi. In 1990 he founded the String Quartet of Tokio, with Kuribayashi, the tsugaru shamisen player Michihiro Satoh and the guitarist Koichi Hiroki, then expanded it into an eleven-piece orchestra that added sho, hichiriki and biwa. For TAO's staging of White-Whiskered Lear he assembled seven koto players around his bass, and the music was recorded as Blue Poles of Lear (TAO, 1992).

Korea changed his rhythm. In May 1992 he and Umezu traveled to Chindo and Seoul to record with Korean shamans, an encounter that produced a track on Umezu's Shin Myong (JVC, 1992) and introduced Saitoh to the shaman musician Kim Suk Chul. He organized the first Eurasian Echoes concert in Tokyo in July 1992, conducting a 14-piece band of bass, oboe, guitar and Japanese and Korean traditional instruments playing his compositions, and took the project to Seoul in 1993 and 1994 with the pianist Fumio Itabashi and the koto player Kazue Sawai. Itabashi's album Tuki-no-tubo, recorded at Kuchu Sampo Kan in December 1992 with Saitoh and Sawai among the players, appeared in 1993, and the same name was given to the Tsuki no Tsubo trio of Saitoh, Itabashi and Sawai, which toured Korea, Laos and Thailand in November 1994. Eurasian Echoes was later performed in Japan, Korea and Singapore.

From 1994 Europe became a second home. That year he and Sawai formed the group Fifth Season with Phillips, the percussionist Alain Joule and the soprano saxophonist Michel Doneda, toured France, Belgium and Switzerland, and in August he took part in the Avignon International Contrabass Festival directed by Phillips. In 1995 he formed the trio ARC with Doneda and Joule. The partnership with Doneda lasted roughly thirty years and produced the long-running Spring Road duo series. On October 13, 1996, at the Yokohama Jazz Promenade Festival, he played a duo with Joëlle Léandre, released by Omba Records in 1998. In October 2000 he recorded across Japan in a bass trio with Phillips and Ino, which became October Bass Tri-logue. On May 23, 2003, at the Festival International de Musique Actuelle de Victoriaville in Quebec, he joined Phillips, Léandre and William Parker for a four-bass set dedicated to the memory of Peter Kowald, released as After You Gone; four days earlier he had played the same festival in a quintet with Doneda, Sawai, the guitarist Kazuo Imai and the percussionist Lê Quan Ninh.

At home he built an infrastructure of his own. His Travessia label began with Orbit 1 (TRV-001) in 2006 and reached Travessia (TRV-020) in 2016, documenting his duos with the guitarist Kazuo Imai and the violinist Naoki Kita, his encounters with Doneda and Phillips, and his partnership with the German bassist Sebastian Gramss, with whom he recorded Raku on a German tour in June 2013. He appeared at the Hawai'i Contrabass Festival in Honolulu in 2006, played solo at ORT in Wuppertal in 2010, and worked repeatedly with the dancers Jean Sasportes and Ryotaro Yahagi, including projects with disabled performers. Other work included two double concertos for the Kanagawa Philharmonic, five television programs about improvisation for NHK, and lectures at Sophia and Waseda universities.

His last decade was shaped by song. With Kita on violin and the vocalist Junko Satoh he formed the Looking for Songs trio, which recorded Flooded Forest and Mugasariuta in 2010 and 2011 and a live album from the Pole Pole Za space in Tokyo in 2012. Its tango-flavored song cycle Operita, released in 2016 as a CD and DVD recorded at the Gewand Hotel in Hiroshima, was written while he was mourning his mother's death.

In April 2016 he recorded a session at Radio France in Paris with Doneda and the pianist Frédéric Blondy, which came out in 2021 as Spring Road 16, his first posthumous release. He celebrated his 60th birthday with a solo concert at Sonorium in Tokyo on July 8, 2016, released as Travessia, and described it as a possible fresh start; soon afterward cancer symptoms limited his activity for several months. He kept working, and his last video collaboration was with the traditional musician Shun'ichiro Hisada. Tetsu Saitoh passed away on Saturday, May 18, 2019, shortly before noon. Free Jazz Blog's obituary quoted his credo: "I will always try to sing my own song."

Saitoh played an 1880s bass he had found in Belgium, a lion-head instrument that he said was famous for its carved scroll, and he was known for unusual tunings and for techniques he taught to younger bassists. His solo playing leaned on gut strings, harmonics, extended bowing and prepared bass, with percussion (a Korean gong, the ching) often within reach. He described improvisation in terms of three elements, now, here and myself, and saw the pursuit of free improvisation as a road toward what he called "anonymous universality."

The repertoire around that core was unusually broad. There was Piazzolla and nuevo tango, including a reading of "Escualo" on Travessia; Brazilian choro, with Pixinguinha pieces on Choros & Improvisations Live (2016, with the saxophonist Taiichi Kamimura) and Baden Powell's "Berimbau"; the Bach Cello Suite No. 6 Allemande; "Baron Mingus," a swinging original quoting Charles Mingus; and "69Q" by Anthony Braxton, which the Ohrai Trio played on Clouds Move (2000). He also drew on Korean shamanic music (Kim Suk Chul and the Chindo musicians), Okinawan and Yaeyama folk songs, gagaku and koto music, butoh and theater.

His relationship to the word jazz was complicated. In a 1992 interview in the magazine Jazz Hihyo, he recalled being asked abroad why a Japanese musician played jazz, said he did not think he had been playing jazz, and added that traditional Japanese instrumentalists understood him better than jazz musicians did. His records nonetheless sit squarely in the jazz and free-improvisation world, filed under jazz on Discogs, released on labels such as Les Disques Victo and Relative Pitch, and reviewed in the jazz press. This profile treats him as a free-jazz and improvised-music bassist whose work absorbed a large share of the world's folk traditions, rather than the other way around.