The Dave Smith Instruments Poly Evolver Rack represents Dave Smith's triumphant return to hardware synthesizers and stands as a benchmark for sonic ferocity. This rack-mounted powerhouse is essentially four complete Evolvers in a single rack space, offering unprecedented flexibility as a four-voice polyphonic synthesizer, four independent mono synths each with its own sequencer, or any combination in between.

At its core, the Poly Evolver Rack is a true analog/digital hybrid instrument featuring four oscillators per voice—two digitally controlled analog oscillators and two digital wavetable oscillators. The digital oscillators incorporate the legendary wavetables from the Prophet VS, while the analog oscillators deliver multiple classic waveforms with pulse-width modulation and hard sync capabilities that sound remarkably rich and substantial.

What truly distinguishes the Poly Evolver Rack is the seamless integration of its analog and digital personalities. Rather than simply adding digital effects at the end of the signal chain, the digital processing is tightly woven with the analog electronics throughout a true stereo signal path. Classic Curtis analog low-pass filters and genuine analog VCAs contribute warmth and body to the analog section, while digital high-pass filtering, tuned feedback, and digital distortion add sizzle and edge. The instrument features bit crushing, synced delays, and the ability to process external audio, with separate stereo outputs for each voice.

A standout feature is the true stereo signal path for each voice. The left and right channels receive their own independent analog oscillator, lowpass filter, highpass filter, VCA, and effects, enabling sophisticated stereo imaging effects. The instrument effortlessly transitions from thick analog smoothness to crisp digital aggression—or anywhere in between. The LFOs, step sequencer, and three separate delays can all sync to MIDI for complex, evolving, rhythmic, time-based effects in true stereo.

In Program mode, all four voices play identical sounds. Combo mode offers complete flexibility: stack all four voices for massive unison sounds, split or layer the keyboard in any configuration, or play one or more sequences simultaneously. Each voice can respond to a different MIDI channel, and multiple Poly Evolver Racks can be daisy-chained for expanded polyphony.

The Poly Evolver Rack excels at external audio processing, with stereo audio input routable to any or all voices for parallel processing of external stereo or mono signals. The output of one voice can even be routed to another's input for creative double-processing effects.

While designed primarily as a studio instrument meant to be tethered to a computer-MIDI setup, the Poly Evolver Rack ships with the Soundtower editor/librarian for both Windows and Mac OS X. It's also compatible with programs like MOTU Unisyn for accessing, editing, and controlling all parameters. The hardware interface features highly accessible sound control with 78 knobs and 58 switches, complemented by clocked, pulsing blue LEDs and elegant hardwood end-panels.

This is a sound designer's dream instrument capable of everything from ultra-creamy to ultra-aggressive tones with the turn of a knob—massive doesn't even begin to describe its sound.

Technical Specifications

Architecture

• Four-voice polyphonic analog/digital hybrid synthesizer
• Each voice is a complete Evolver with independent processing
• True stereo signal path with separate processing per channel
• Ressurects oscillator, filter, and component technologies from Sequential Circuits Prophet-VS and Pro-One

Memory

• 512 fully editable Programs (4 banks of 128)
• 384 Combos (3 banks of 128)

Oscillators (per voice)

• 2 digitally controlled analog oscillators (DCOs) with:
  • Selectable sawtooth, triangle, saw/triangle mix, and pulse waves
  • Pulse-width modulation
  • Hard sync
  • Independent glide (portamento) rates per oscillator
• 2 digital wavetable oscillators with:
  • 96 Prophet VS wavetables
  • 32 user wavetables (loaded via MIDI only)
  • Wave sequencing capability
  • FM synthesis
  • Ring modulation
• White noise generator

Filters (per voice)

• 2 analog Curtis low-pass filters (one per stereo channel)
  • Selectable 2-pole and 4-pole operation
  • Self-resonating in 4-pole mode
  • Fully resonant
• Digital high-pass filter per voice

Amplification

• Real analog VCAs per voice

Modulation (per voice)

• 3 envelope generators (four-stage ADSR):
  • Filter envelope
  • VCA envelope
  • Assignable envelope
• 4 LFOs
• All LFOs and delays MIDI-syncable

Effects (per voice)

• 3 separate, syncable, stereo delay lines
• Tuned feedback with "Grunge" (feedback as pitched sound source)
• Digital distortion and "Output Hack"
• Bit crushing
• Independent effects per voice (feedback, delay, distortion, high-pass filter)

Sequencer

• 16-step, 4-parameter analog-style sequencer per voice
• MIDI-syncable
• Each patch stores its own sequence
• All four sequences can play simultaneously

Modes

• Program mode: all four voices play the same sound
• Combo mode: voices can be stacked, split, layered, or independently allocated
• Each voice can respond to a different MIDI channel
• Multiple units can be daisy-chained for increased polyphony

Audio Routing

• Stereo audio input can be routed to any or all voices
• Parallel audio processing of external stereo or mono signals
• Voice output can be routed to another voice's input for double-processing effects

User Interface

• 78 knobs (endless-turn encoders)
• 58 switches
• Clocked, pulsing blue LEDs
• Hardwood end-panels

Connections

• MIDI: In, Out, Thru, and Poly Chain
• Stereo audio input: 1/4″ unbalanced
• Main stereo audio output: 1/4″ unbalanced
• Separate stereo outputs per voice (4 pairs): 1/4″ unbalanced
• Headphone output: 1/4″ stereo phone jack
• Sustain pedal input: accepts normally on or normally off momentary footswitch
• Pedal/CV1 and Pedal/CV2 inputs: responds to expression pedals or control voltages ranging from 0 to 5 VDC (protected against higher or negative voltages)

Format

• Single rack space (1U) rackmount unit

Software

• Ships with Soundtower editor/librarian for Windows and Mac OS X
• Compatible with MOTU Unisyn and other editor/librarian software