SeM20st

Stereo SEM20 Filter

The SeM20st is a stereo version of the first module bubblesound put out, the SeM20. It has become one of the classic filters in the Eurorack world. The SeM20st is the most versitle analog stereo filter on the market today.

The inputs on the Left side are all normalized to the Rght, so one input can be turned into a stereo signal. There is an Offset for the Left Cutoff, this allows a wider stereo field and is especially useful if the input is coming from a mono source. The CV inputs on the Left can also control the Cutoff and Resonance of the Right side. The Right side CV Cutoff pot is an attenuvertor, when it's at noon it's off, turn clockwise from noon the pot acts like a normal attenuator, gradually adding the CV to the Cutoff. When it's turned counter-clockwise from noon the CV is inverted, acting like an inverted ADSR. This can be used with a single LFO into the Left Cutoff CV to create a sort of ping-pong with the 2 sides, as the Cutoff goes up on one side it goes down on the other.

The Resonance section is exactly the same as in the SeM20, but with the Stereo version the Resonance is controlled by a VCA, allowing for CV control of teh Resonance. The Resonance CV will work with either an LFO or an Envelope.

Outputs: Channel has 4 outputs available; Low, Band, High and Notch Passes. The Notch Ballance pot sweeps from Low Pass to High Pass and can produce some really nice phasing .

https://www.bubblesound-instruments.com/