Doepfer A-138 a/b Mixer (linear / logarithimc) - Manual

doepfer System A - 100 MIXER A-138
1
1. Introduction
Module A-138 (MIXER) is a four channel mixer, which
can be used with either control voltages or audio si-
gnals.
Each of the four inputs has an attenuator, and there’s a
master attenuator, so that the mixer can be used at the
end of the audio chain - ie. it can be used to interface
directly with an external mixer, amplifier, etc..
The module can be supplied in two versions:
• A-138 a: potentiometers with linear response, so
especially suitable for control voltage mixing.
• A-138 b: potentiometers with logarithmic response,
so especially suitable for audio signal mixing.
From about middle of 2004 the module is equipped with
an additional offset function for input 1. An internal
jumper is used to decide if control input 1 works as a
positive or negative DC offset generator provided that
no plug is inserted into input 1.
Input 1
Output
A-138
MIXER
Input 2
Input 4
Input 3
In 1
In 2
In 3
In 4 Out