The signal is the essence of sound and digital image: from the invisible material information to the naked eye, codified and flowing through the filmic technologies of the age of the Web. Its access, of paramount importance, is in protected mode (Friedrich Kittler). On one side digital tools are built as black boxes in the middle of which the signal processing is carefully rendered opaque and inaccessible. On the other, private companies and governments of the intelligence services have unlimited technological power of interception and investigation of signals to conduct their surveillance and profiling globally. Rejecting this paradox, some artists like Pierre-Yves Cruaud, HC Gilje, Paolo Gioli, Benjamin Muzzin, Jacques Perconte, Leighton Pierce, Joost Rekveld, Sadia Sadia, Jerome Schlomoff, develop signal intelligence: they thus pass its regulated treatment according to the standards of audiovisual experimentation to release the untapped plastic resources and express all the strata of the artist's sensibility.