Bubblesound SEM20 MKII Dual Eurorack Multimode SEM Filter Module

SEM20 is dual multimode filters inspired by the SEM filter, but with added resonance so it actually self oscillates!  Also features four inputs that can be summed in any combo to the two filters, allowing things like use as two filters, one set of two types like high pass into low pass, or using both side by side for true stereo filtering.  Huge vintage sound!

Input Section

The Dual version has a 4 input mixer section. Each channel can be assigned to either filter, to both for either stereo filtering or to get the Korg MS-20 or OSCar dual filter effect. The 4 input mixer and 8 outputs make feedback loops and self oscillation patches extremely easy and almost required. 

When the input is at 5(noon) it's full volume. Beyond 5 the filter will begin to overdrive and distort, just like the original SeM20.

Single/Dual Switch

In Single Mode both filters act independently with their own Freq pots and 2 attenuated CV inputs each. They are 2 full featured SeM20 filters in one module. In Dual mode the upper Freq pot and CV 1.1/1.2 control both filters. This is great for stereo filtering and would work especially well with the new stereo effects from Audio Damage. There is an offset pot for the second filet when it's in Dual mode and this works like the spread feature on the OSCar. You can feed the same input to both filters, offset the second one and then use the 1 CV inout or the Freq pot to sweep both.

This filter can go from a very smooth Oberheimy sound to aggressive, overdriven acid dipped screeching . 

It doubles as a pretty good kick drum, too.

Features:

• 12db High Pass, Low Pass and Notch filter
• 6db Band Pass
• Self oscillation when the High Pass is fed into the input
• 4 cv frequency inputs with attenuators
• Notch Pass balance sweeps between High and Low Pass

Specifications:

width: 16hp

current draw: 70mA