This module comprises of an 3 Way Audio Input Mixer, A Control Voltage Input Mixer, A 24dB/Octave Voltage Controlled
Filter with 4 tapped outputs, 2 Voltage Controlled Amplifiers and Control Envelope Generators. Bar one 'buffer' IC- the
circuits are all discrete transistor, resistor and capacitor based. Just like the X-Series Dual Oscillator- the resistors are
all half watt carbon types and the capacitors are a mix of ceramic/mylar types. The result of this design is an extremely
warm and vibrant module. From the bass end up- the sound is consistently clean but full...this is down to pure
discrete transistor design and PCB layout.

A Response Switch sends the Filter Output into the first VCA and the choices are 1 pole (6dB/Octave)/
2 Pole (12dB/Octave)/ 3 Pole (18dB/Octave) and the classic 4 Pole 24dB/Octave response.
 
A second VCA can be externally controlled for the final output and lends itself to AM applications
and other Voltage Controlled Volume applications.

As can be seen- all four responses can be tapped out via jack sockets and these are pre- VCA outputs.
Each Envelope Generator provides control outputs- the VCF EG sports two outputs- both positive and negative.
There is also a dual switch- providing both Momentary Trigger and Hold.

Why 'Backend'? Effectively this combo module is like the backend of a classic analogue synthesizer. It has all the
functionality of a full synth but just lacks the sound sources- all this in a compact 42hp 3U size!

I have recorded some deomos using this protype module and you can here it in action with the 
X-Series Dual Oscillator on that page!

...click here for more sounds!