QuadraSID offers far more than a simple emulation of the SID chip. Enriched with many new functions e.g. an arpeggiator, four LFOs, wavetables and a eight fold oversampling, this software instrument offers unlimited sonic possibilities, and surprises even the most experienced SID professional by its flexibility.

Features:

* Up to four independent SIDs can be emulated with a single SID plug-in.
* Each SID has three independent oscillators and a fourth "Galway-noise" channel.
* Lofi, Normal and Hifi render modes.
* Chip-Model selector per chip (6581 / 8580).
* The SID emulation has been enhanced so each oscillator can have its own volume.
* Built-in arpeggiator for each oscillator.
* Four LFOs, four envelopes and four "functions" for each oscillator.
* Programmable wavetables for each oscillator.
* Three play modes: Mono, Poly & Multi-timbral.
* Nearly every parameter can be modulated by MIDI or other internal modulators.
* Velocity sensitive Virtual-keyboard can be toggled on/off.
* Beta-tested by Chris Hülsbeck, the C-64 SID guru.
* Very low CPU consumption.

More info
http://www.kvraudio.com/get/92.html