Dupertuis Electronique SA

Fusion VCO2 is a full analogue sound source with lots of distinct features.
Features

Full analogue design
Great tracking over 8 octave range
Detune function for thickening the sound
-1 oct transistor based suboscillator
Tube overdrive circuit
External audio input
VCO synchronization
Simultaneous waveform outputs

The core of the module is highly stable AS3340-based VCO with three simultaneously available waveforms, transistor-based suboscillator and detune function – two BBD delay lines that make frequency shifter that is mixed back to the principal oscillator in order to emulate two detuned VCOs.
Tube crunch – distinct tube overdrive – is added on the top of the mix. Furthermore, Audio input mixes an external audio signal with the principal oscillator which results in crazy sonic experience.
Fusion VCO2 is exactly what you need, if you wish to get really low frequencies and have a sound that sets your modular system apart from mass!
The Erica Synths Fusion VCO 2 offers a very wide range of sounds.
If you simply need an oscillator without the specific tube sound, you have access to it via the triangle and pulse outputs.
The Erica Synths Fusion VCO 2 is not a standard oscillator, but thanks to the two tube stages, it is in itself a module capable of diverse sound shaping.
If you are looking for warm, fat or even heavily distorted sounds, you should definitely take a look at the Fusion VCO 2, because there is hardly any analogue oscillator available that offers so much of its own sound character and works both for long sustained and percussive sounds. 
Without question it is worth it in terms of both sound, functional possibilities and processing – Pro Audio
Features

Audio input level 10Vptp
Audio output level 10Vptp
VCO range C0-C8 and more
PWM CV range (full span) -5V – 5V
Panel width 14 HP
Module depth 42 mm
Power consumption 228mA @ 12V, 55mA @-12V