Vinca by Instruo is a two-channel VCA whose two units can be operated in parallel or in series. Each VCA is designed differently, so they cover different functions while complementing each other. The upper VCA has bias and input attenuator controls over its four-quadrant multiplication, which basically makes it a ring modulator as well. The lower VCA works in the usual way and can additionally be continuously adjusted in curve characteristics from linear to exponential. The linear processing benefits control voltages to be processed, the exponential one is more suitable for audio signals. An additional mode switch selects whether the two VCAs are operated in parallel, i.e. each separately, or in series. In the second configuration the lower VCA processes the output signal of the upper one. Via rear bus cable several Vinca modules can be interconnected to provide mixing and routing arrays for larger systems.