SUM is a 26 HP 7 Channel Eurorack Mixer with EQ, Pan and Aux Send.

Each of  the 5 mono channels have a VOLUME, EQ, SEND and PAN potentiometer and may be MUTED with a switch. Additionally the GAIN can be adjusted using the little trim potentiometer located above each VOLUME pot. Turning the SEND pots will route the signal to the SEND jack in order to integrate external effects. The wet effect signal may be returned in stereo using the REL and RER jacks.

The EQ will boost high frequencies and cut low frequencies when turning the pots clockwise and vise versa turning them counterclockwise.

Channel 6 and 7 are made for stereo signals (left & right). Their VOLUME can be changed with the STL/R potentiometer.

The sum of all channels is available in stereo on jacks STL and STR and is also being routed to the STEREO OUT (large jack). The Volume of this output may be adjusted with the STEREO VOL potentiometer. This output is suitable for headphones.

In case you want to use single outs, there are solder joints for all channels, aux send and the stereo sum on the bottom side of the PCB. This is really helpful if you want to install separate outputs on the back of your case.


The module consists of two boards:


Mixing with SUM (4:33)

ST Modular 2018

Gallery SUM

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