ES-1

Audio/cv Interface

The ES-1 offers the following advantages over directly connecting an audio interface to analogue gear for CV control:
No requirement for the interface to be DC-coupled.
No need for special cables (e.g. TRS to TS 'floating ring' cables).
No danger of damage to the interface - the ES-1's inputs are completely standard balanced audio inputs.
Much greater output voltage range - up to 9x more than directly connecting a DC-coupled interface via a 'floating ring' cable.
Specifications
There are two standard configurations of the ES-1:
Jack inputs - the eight inputs are presented on 1/4" jack sockets, which will accept balanced or unbalanced jack leads.

the module is 70mm deep.
The front panel is drilled for both Doepfer and Analogue Systems mounting holes (using a 'slot' rather than a single round hole).
The power connector is a Doepfer standard 16 way IDC, with -12V at the bottom edge of the board.
The unit consists of 8 identical channels. Each channel consists of
A balanced input stage, capable of accepting balanced or unbalanced inputs.
Note that for audio interfaces with differential balanced outputs
this immediately gives you double the voltage range of using a direct DC connection from the interface.
An optional rectifier circuit, for use when the audio interface is not DC-coupled.
A jumper on the PCB connects or disconnects the rectifier.
An output amplifier and DC offset circuit. This has a gain range of approximately 1x to 4.5x.
The DC offset is adjustable, to centre the output of the rectifier circuit around 0V (if desired).
Current draw is 43mA on each of the ±12V rails (i.e. 86mA total).

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