The Zlob Modular Attenumixer is a three channel passive attenuator with a sum. Each channel is normalled to the sum(VI) so it can be used as a 2 channel mixer and 1 channel attenuator, or a 3 channel mixer, or as 3 separate attenuators. Normalization to the sum is broken by inserting a jack into the outs of channels I-III. The Attenumixer works well with both cv and audio, although the potentiometers have a linear response. Since this module is passive there will be some amount of signal loss with the sum out.