Module A-138n is a simple four channel mixer, which can beused with either control voltages or audio signals. Each of the four inputs has anattenuator with a linear response curve available. The amplification range is0....1.The output is twice available (two sockets,hard-wired like a multiple). 

The module is the slim version of module A-138aand offers nearly the same features.But the distances between the controls are smaller and rubberized small-sizedknobs are used. In return the front panel has 4 HP only which is half the widthof the A-138a. The module is primarily planned forapplications where only limited space is available.The main functional difference compared to the A-138a is the missing attenuator for the(dual) output. And input #1 does not feature the DC offset option.