Les Double Six, billed in the United States and on several records as The Double Six of Paris, was a French vocal group founded in 1959 by the singer and pianist Mimi Perrin. It sang jazz in the manner of vocalese: Perrin took the arrangements and solos of American big bands and small groups, wrote French lyrics that fitted them note for note, and had each singer take the part of an instrument. The name came from the studio method, in which two layers of a sextet were recorded over one another so that the result sounded like twelve voices. The group made four albums between 1960 and 1964, its membership changed from session to session, and it came to an end in 1966.

Perrin was born on February 2, 1926 in Saint-Maurice, near Paris, studied piano as a child and took an English degree at the Sorbonne. She caught tuberculosis in 1949 and spent time in a sanatorium; afterwards she played in the cabarets and clubs of Saint-Germain-des-Prés with her own trio and sang in the Blue Stars of France, the vocal group around Blossom Dearie. She also worked as a studio backing singer, and French Wikipedia says that her session work for Henri Salvador led to her meeting Quincy Jones. Her model for the new group was the American trio Lambert, Hendricks & Ross, and French Wikipedia says she found French less suited to the style than English, which makes the closeness of her lyrics to the original solos more striking.

The first record, Les Double Six Meet Quincy Jones, came out on Columbia in France in 1960 and was recorded at the Théâtre des Champs-Élysées in Paris. It puts French words to eight pieces by or associated with Jones, among them "Stockholm Sweetnin'", "Evening in Paris" and "Boo's Bloos", with Perrin, Christiane Legrand, Claude Germain, Jacques Denjean, Jean-Claude Briodin and Ward Swingle singing, and with Art Simmons on piano, the bassists Michel Gaudry and Pierre Michelot and the drummers Christian Garros, Daniel Humair and Kenny Clarke. A sticker on the French sleeve records the Grand Prix du Disque of the Académie Charles Cros, and Capitol released the album in the United States in 1961 as The Double Six of Paris. A four-song EP of 1961 followed with Georges Arvanitas on piano, then the LP Swingin' Singin' in 1962, which turns recordings by Count Basie, Woody Herman, Gerry Mulligan, Miles Davis and Charlie Parker into French, and gives the one solo vocal feature to John Coltrane's "Naima", sung by Perrin.

In 1963 the group recorded with Dizzy Gillespie. Wikipedia dates the Paris sessions to July 1963, with Gillespie, Bud Powell, Michelot and Clarke playing first and the Double Six singing over the tape afterwards, and a second session in Chicago in September with James Moody, Kenny Barron, the bassist Chris White and the drummer Rudy Collins. Lalo Schifrin wrote the arrangements, Perrin the French lyrics, and the album carries twelve pieces from the Gillespie repertoire, from "Emanon" and "Tin Tin Deo" to "Con Alma" and "Ow". Leonard Feather gave it five stars in DownBeat. The fourth album, The Double Six of Paris Sing Ray Charles (Philips, 1964), has an American rhythm section led by the tenor saxophonist Jerome Richardson, with Bobby Scott on piano and vibraphone, Milt Hinton on bass and Osie Johnson on drums, and arrangements by Billy Byers and Melba Liston. It was nominated for a Grammy Award in 1965 in the vocal group category, which went to the Beatles.

The singers moved in and out. Swingle, an American who had lived in France since 1951, left to found the Swingle Singers, who were established by 1962 and began by singing Bach in the same scat style; French Wikipedia lists Germain, Briodin, Claudine Barge (later Meunier) and Hélène Devos among the Double Six alumni who later sang with them. Besides the singers named on the records, Wikipedia lists the trumpeter Roger Guérin as a member, and Eddy Louiss, who joined by 1961, sang and played vibraphone with the group before he became known as an organist. In 1965 Perrin's health failed again and she tried to put together a new sextet with Bernard Lubat, Jef Gilson, Gaëtan Dupenher, Annie Vassiliu and Hélène Devos; its record was never released, and AllMusic says that Gilson tried to hold the group together until it split in 1966.

Perrin left music and from 1972 worked as a translator, rendering novels by John le Carré, Alice Walker and others, and the autobiographies of Dizzy Gillespie, Nina Simone and Quincy Jones, into French. She passed away in Paris on November 16, 2010. The group's early records were gathered on the 1999 RCA Victor compilation Les Double Six, which holds the whole of the 1960 and 1962 albums, and Dave Hughes, reviewing it for All About Jazz, placed the sextet among the best vocal jazz ensembles of the past half century.

The method was strict. Perrin transcribed the instrumental lines and solos from existing recordings, set them for six voices, and wrote French words that carry the rhythm and the vowels of the original phrasing, sometimes humorous and sometimes poetic, so that a voice stands for a trumpet, a baritone saxophone or a trombone rather than telling a story. The result sits between swing-era big-band singing, bebop and the cool jazz of Mulligan and Davis, which is also the span of its repertoire. The model was the American trio Lambert, Hendricks & Ross, which was reaching its audience at the same time, and the sextet in turn became the model for the Swingle Singers; one reviewer ranks it with Lambert, Hendricks & Ross, the Manhattan Transfer and New York Voices.