Moppel has recently released a new free virtual synth called Sonitarium.

It employs a variant of DSF synthesis with aliasing-free oscillators that generate a quadrature stereo signal. Providing up to 100 oscillators per voice, Sonitarium is most suitable for smooth pads, layered leads, and some oddities.

Features :

• Aliasing-free DSF oscillators, each generating a quadrature stereo signal.
  
• Up to 100 oscillators per voice. Unison controls to alter the pitches and phases of the oscillators.
  
• Freely selectable polyphony with up to 16 voices.
  
• Text field input for all controls.
  
• Envelope and key tracking controlled volume. Adjustable pitch bend range.
  
• Freely adjustable Attack, Decay, and Release slopes.
  
• MIDI control of all parameters (CC).
  
• 60 presets.

Sonitarium is available now as a VSTi for Windows and it's free.