 This synthesiser was well-adapted to the production of continuous and complex sounds using intermodulation techniques such as cross-synthesis and frequency modulation but was less effective in generating precisely defined frequencies and triggering specific sounds .The Coupigny synthesiser also served as the model for a smaller, portable unit, which has been used down to the present day .In 1966 composer and technician François Bayle was placed in charge of the Groupe de Recherches Musicales and in 1975, GRM was integrated with the new Institut national de l'audiovisuel (INA – Audiovisual National Institute) with Bayle as its head.