The I-o47from Instruo is an analog Multimode filter, which is based on the classic 1047 from ARP 2500 and has been expanded and improved in several points. The module impresses with four filter characteristics that can be tapped in parallel, which sound clean and have a pleasant resonance behavior. Lowpass and highpass have a slope of 18dB, the bandpass varies between 6 and 18 dB, which depends on the set resonance in this circuit. Notch is with a variable Offset in the range of +/- two octaves which is also sufficient for phaser-like sounds. The audio input turns out a bit more extensive than usual. The upper input can be influenced by the gain control and can be limited with Limit if needed, so there will hardly be any overloads of the filter circuit. The level of the signal applied to the inverted input is inversely proportional to the level of the resonance parameter. As resonance increases, the signal applied to this input decreases. To control the filter there are four CV inputs for tracking, FM (with attenuverter), notch & resonance (Q). The Strike input pings the filter, strictly speaking an incoming gate or trigger signal sets the resonance to maximum.