The Access Virus Rack is a 16 voice multi-timbral analog modeling rack-mount synthesizer. It has 2 oscillators and one sub-oscillator per voice. The Virus Rack also has a noise generator, ring modulator, two multi-mode filters, two envelopes, a stereo VCA, and a saturation stage for cascade filtering, tube, and distortion effects. There is a random patch generator which allows for new patches to be automatically created or for modifying existing patches. Two external inputs allow processing of external devices through the filters, gates and lo-fi effects. External audio sources can also be used to modulate frequency and ring modulation. Software Version 2.0 adds an additional 512 presets by replacing the demo song included in the original software version. The Virus Rack was first released in 2001 by Access Music of Germany..