The first Modular System 11’s were built in 1976 by RSF, a French synth-maker founded by two brothers: Ruben and Serge Fernandez. The sound, build quality and reliability of the machines made the systems’ reputation. Altogether about twenty modular systems were sold, accounting for a total of more than 300 modules.
Later distilled into a keyboard version under the ‘Kobol’ name, the System 11 became fully-featured, allowing it to make its way to professional musicians including Jean-Michel Jarre, Kate Bush, Vince Clarke, Bernard Szajner, Vangelis, Peter Gabriel and many others.