Opak starts in 1999 in Vevey (CH) when Arnaud Sponar joins Julien Grandjean for a new common musical project. They already know each other for a long time, since their first pop-rock bands in the early 90's.

Month after month they create their first instrumental pieces : a mix of electronic sequences and samples, guitar and bass (Julien), jazzy drums, percussion, piano, tapes and dictaphones (Arnaud).
Gradually they find their common musical field and the elements of their sonic alchemy :
hypnotic atmospheres, energy of real instruments, experimentation on sound and noise.

In 2001 they do their first concerts, both playing their instruments along the computer tracks. The first shows are enhanced by pyrotechnics, replaced since 2003 by video projections by Thanassis Fouradoulas.

Playing a concert at l’Usine in Geneva in 2002, Opak gets a deal to release its first album on Urgence Disk. In March 2003 they release "Prolog" : 7 tracks, 71 minutes, a completely self-produced home-made work.
An album without any compromise that got good reviews in the press.

Following this release, Opak do some more concerts, remixes for other swiss musicians, soundtracks for 2 short-films, and start (self-) recording new tracks for the next album.
Again they produce it themselves, having no budget for studio or mastering. At the time of having all the tracks for the album, they get a deal to release it on Creaked Records, a label in Lausanne.
This is “Two sleepwalkers on a tight-rope”, released on CD and vinyl (2LPs) in May 2005.