Labrosse was gravitating toward L'Enfant Fort and the Pouêt Pouêt Band, collectives of left-field musicians that predate the beginnings of Ambiances Magnétiques. There she met saxophonist/singer Hétu and drummer Danielle P. Roger and together they formed the all-girl group Wondeur Brass. Her quirky keyboard playing, which made use of unusual post-new wave sounds, gave the band its signature on the two LPs Ravir (1985) and Simoneda, Reine des Esclaves (1988). The trio also performed under the name Les Poules, recording one album in 1986 (the unit was revived as an improv project in the early 2000s) and with bassist Marie Trudeau as Justine in the early '90s, Labrosse's closest brush with fame, at least in Eastern Europe where the group built a cult following.
In 1985, along with her colleagues, she was asked to join Ambiances Magnétiques. There she developed a special affinity for drummer Michel F. Côté both in and outside music. She contributed to his first two Bruire albums (especially Les Fleurs de Léo), recorded a duo CD with him (Duo Déconstructiviste), and together they wrote the music for Robert Lepage's play +La Géométrie des Miracles (Geometry of Miracles) and toured with his technological cabaret +Zulu Time.
Labrosse released her first solo CD, Face Cachée des Choses, in 1995, at the end of Justine's career and before joining Hétu's new group Castor et Compagnie. It focused for the first time on the sampler as an instrument, a soft-noise direction she would stick to from then on. Île Bizarre (1998) with Ikue Mori and Martin Tétreault revealed her work to an international audience. With Tétreault, she toured Europe and eventually released the duo CD Parasites (2001). ~ François Couture, Rovi