Roland's System-100m, which was built from 1979 to 1984, is probably one of the best known modular systems. The manageable number of modules and especially the presence of several functions per module made it an attractive instrument for many users. Behringer has transferred the classic dimensions to the compact Eurorack format and has taken great care to ensure that sound and function are in no way inferior to the cult object

The Behringer 173 Quad Signal Gate / Multiple contains six multiples, each with four interconnected sockets. This allows three copies of a signal to be made for each multiple. In addition, there are four similarly constructed signal gates; these are able to switch incoming (audio) signals on or off. The sockets that trigger the switching accept CV and gate signals and open the channel when the voltage on the positive edge is sufficient and close the channel when a voltage triggers the negative edge.