With Cynthia you can do all that crazy stuff you cant do with a modern synth.

Cynthia is monophonic VSTi, very Old School, but will still be able to keep in tune throughout the song, patches can be stored and it is of course fully MIDI controllable.

Control voltage and sound sources:

3 monophonic oscillators with controls for shape and level of the waveforms, sync and phase-shift
Noise generator
Two audio inputs so you can modify the sound of a guitar or your voice
8 step control voltage sequencer

Attack-hold-decay(-repeat) envelope generator producing a control voltage with adjustable level and bias

Treatments:

A self-oscillating filter (can be used as a sine OSC as well)
3 VCA's controlled by the envelope generator or control voltages assigned to the output level of each channel
Ring modulator
Spring reverb with short and long spring
Delay (delay time from 0 to 10 seconds)

Controls:

Tuner for tuning OSC's by ear
Joystick for extra control
16 x 20 routing matrix with inputs for host MIDI pitch and velocity and inversion of individual connections
MIDI cc's can be assigned to any knob
Adjustable portamento time
Trigger button for triggering the envelope generator

Outputs:

2 pairs of stereo outputs with extra filters, pan and volume control, direct out and speaker (simulating the sound of a pair of canny speakers)