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Doepfer A-135-1 Voltage Controlled Mixer Re-Design

Old version of the A-135
The original A-135 module was a simple quad voltage controlled mixer.
It was made of 4 independent linear VCA's, mixed to one common output.
For each VCA the following inputs and controls were available: audio input with attenuator, control voltage input with attenuator, gain (pre-amplification).
The VCA's were realized with high-quality CEM VCA's (CEM3381).

The module could be used for voltage controlled mixing of up to 4 audio signals with separate control voltages (e.g. by LFO's, ADSR's, Random, Shepard generator, MIDI-to-CV interface or other control voltage sources).

In June last year, Doepfer announced the re-design of several modules because of shortage of CEM3080 Chips that were used in this A-135 and other modules.
This year a few of these re-designed modules were released, each in a slightly extended/ improved version (like the A-130/131 that are now also DC-coupled, and the recently announced A-141-2).*

A-135-1 Redesign of the A-135
This new version of the A-135 also has some nice extras in the form of a Sum Out and 4 single outputs for each channel instead of only one (Mixed) Audio output on the original A-135.
They've also managed to make it only 18 HP instead of  22 HP wide.

The new version of the A-135-1 is also able to process slowly varying control voltages because the signal in/outputs are DC coupled.

The new version is manufactured from May 2013 and is available now.

* More re-designs were also promised to us last year, like the A-107, A-116A-127, A-132-1, A-147, A-171), so that promises a lot for the future...

Find more about various Doepfer re-designs via

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