No matter how many A-138p Input modules are connected, the A-138o Performance Mixer Output adds all of them to one stereo sum which is emitted at separate sockets for left and right. Besides this all signals from the channel auxiliaries are summed, available at the Aux Send socket. The Aux Send level can be adjusted. the effect signal has to return into the mixer somewhere of course, which is handled via the Aux Return mono socket. The Aux Return level is adjustable with a potentiometer.

A-138o features:

• level controls for Left, Right and Aux
• output sockets for Left, Right and Aux (3.5 mm mono sockets)
• A-138o requires at least one A-138p (no stand-alone use)
• Application example for Aux Send and Aux Return: looping in another module for effects (e.g. DSP module A-187-1, BBD module A-188-1, Spring Reverb A-199)
• Application example for Aux Send only: pre-listening in combination with the headphone amplifier module A-139-2

Note: Black versions of the small grey knobs used in this module are available as spare parts. If some of the grey knobs (e.g. Pan or Aux) should be replaced by black ones they can be swapped easily by the customer. If applicable pay attention to order the knobs with 11.5mm diameter (A-100KSB in the price list / section spare parts). Vice versa also the small grey knobs are available as spare parts in case that black knobs of the vintage version should be replaced by grey ones.

The voltage controlled version of the performance mixer is the module series A-135-4.