SUM V2 is an innovative live mixer designed for the Eurorack modular synth ecosystem, featuring AFL listening capabilities.
 
Description / Manual 
Each of the 5 mono input channels has a LEVEL, PAN, EQ, SEND and AFL potentiometer and may be MUTED with a switch. The mono singal will be converted into a pan-able stereo signal. Additionally the GAIN can be adjusted using the little trim potentiometer. Turning the SEND pot will route the signal to a SEND jack in order to integrate external effects. The wet effect signal may be returned in stereo. You can choose between two SEND ways via switch. The send channels can be set to be active either pre or post AFL per channel via a solder bridge. ‚Pre‘ means you can still hear the send/return way when it is in AFL mode (thus the channels signal is actually not audible in the main mix), ‚post‘ means send/return will only work when the channels signal is routed to the main mix. Each SEND channel has a separate GAIN trimmer adjustable from the front.
 
Channels 1 to 5 have an AFL/MIX potentiometer (AFL = after fade listening), which allows you to audit your sounds on the headphones before you add them to the mix. Fully counter-clockwise the channel is only routed to the headphones (AFL), turning it clockwise it will be smoothly subtracted from the headphone out and added to the main mix (Mix). Two LEDs per channel indicate the current state.
 
The MIX TO HP knob routes the main mix output to the headphone out in order to compare the channels that are in AFL mode with the main mix. This can be deactivated with a switch to only audit channels that are currently not send to the main output. The headphone level can be adjusted with the HP VOLUME knob.The EQ will boost high frequencies and cut low frequencies when turning the pots clockwise and vise versa turning them counterclockwise.
 
Additionally there is a stereo input to integrade other mixers, like PHOEBE, SUM or uSUM for example. This channel has no AFL, EQ or SEND.