Odo Synths has released Unknown 64 Pro, which differs from the similarly named freebie Unknown 64 by recreating the sound of the Commodore 64 much more accurately. Unknown 64 Pro is DonationWare.

Features:

• Single oscillator.
• 4 waveforms (triangle, pulse, saw and noise).
• A filter envelope with 3 filter types (lowpass, bandpass and hipass).
• A pitch envelope / pulsewidth envelope and volume envelope.
• Every Envelope can be inverted and has 13 different curves.
• A ring-modulation oscillator or a ring-modulation BPM LFO.
• A BPM LFO for the Pulsewidth, cutoff and oscillator pitch.
• 3 big sequencers for creating the real c64 arps and percussions:
  • One is used for the octave and notes.
  • One only for octaves.
  • One for the waveforms.
• All 3 sequencers are BPM sync with speeds from 1/16 to 1/128. They can be ended at every step or looped.
• Vibrato, bitcrusher, MIDI learn and panner.
• Envelope restart / pickup.
• 128 presets.