The PWM Mantis is a sophisticated duophonic hybrid analog/digital synthesizer that represents the final collaboration between PWM's Paul Whittington and the late synthesizer legend Chris Huggett. This instrument uniquely combines the oscillator design heritage of the classic Wasp synthesizer with the renowned filter architecture of the OSCar, creating a versatile sound design instrument that bridges both East and West Coast synthesis philosophies.

The Mantis features a substantial build quality with a matte-black metal and plastic enclosure weighing approximately 5.3kg. It incorporates 37 full-size, semi-weighted velocity-sensitive keys with aftertouch, providing a premium playing experience. The synthesizer's design philosophy emphasizes immediate accessibility with minimal menu diving - featuring a clear "what you see is what you get" panel layout with just one layer of functionality.

At its core, the Mantis operates as a fully duophonic instrument with two discrete analog signal paths, each featuring its own VCA and VCF. However, it can expand to a unique "quad mode" offering four-voice capability, though with some limitations due to having only two filters. This creates an interesting "dual-paraphonic" structure where the first two notes played receive full filter treatment.

The oscillator section features mathematically generated DCOs designed by Chris Huggett, offering traditional waveforms (sine, triangle, sawtooth, square) plus two distinctive additions: an organ pipe sound that creates psychoacoustically interesting harmonic spreads, and a built-in wavetable with seven harmonically rich shapes. The innovative Shape control extends beyond simple pulse width modulation, adding harmonics to sine and organ waves for FM-like effects.

A standout feature is Oscillator 2's hidden third oscillator accessed via Density and Density Rate controls, enabling super-saw textures while keeping Oscillator 1 available for other duties. The analog filters, descended from the famous OSCar design, provide eight different modes including standard low-pass, band-pass, and high-pass options in both 12dB and 24dB slopes, plus creative Wide Band and Wide Notch configurations.

The modulation system is comprehensive yet intuitive, featuring two LFOs with fade controls, dual envelopes with an additional "sustain fall" stage and cycling capability, and a visual modulation matrix with six destinations. Additional character comes from oscillator drift, ring modulation, and thoughtfully chosen digital effects including four chorus algorithms and Schroeder-type reverb.

The Mantis excels as a sound design instrument rather than a traditional polyphonic keyboard, rewarding users who invest time in exploring its unique architecture and character-rich sonic possibilities.

Technical Specifications

Design Philosophy

• Minimal menu diving with single-layer panel functionality
• No screen interface
• "What You See Is What You Get" (WYSIWYG) design
• Optimized for sound design and creative synthesis rather than traditional polyphonic keyboard duties

Architecture

• Type: Duophonic hybrid analog/digital synthesizer
• Voices: 2 full analog paths, expandable to 4-voice "quad mode"
• Signal Path: Analog (filters, VCAs, effects processing)
• Oscillators: Digital (DCOs designed by Chris Huggett)

Oscillators

• Main Oscillators: 2 DCOs per voice plus sub-oscillator
• Waveforms: Sine, Triangle, Sawtooth, Square, Organ Pipes, Wavetable (WT)
• Shape Control: Per oscillator with modulation input
  • Pulse width modulation on square wave
  • Harmonic addition on sine/organ waves
  • Wavetable navigation on WT
• Pitch Modulation: Dedicated control per oscillator
• Octave Selection: Independent per oscillator
• Sub-Oscillator: Follows OSC 1 parameters
• Density Feature: OSC 2 includes hidden third oscillator with Density and Density Rate controls
• Oscillator Drift: Creates random pitch variations between oscillators

Filters

• Type: 2 analog multi-mode state variable filters with overdrive (1 per voice)
• Designer: Chris Huggett (OSCar-derived design)
• Modes: 8 total
  • Low Pass (12dB/24dB per octave)
  • Band Pass (12dB/24dB per octave)
  • High Pass (12dB/24dB per octave)
  • Wide Band (series configuration)
  • Wide Notch (parallel configuration)
• Controls: Cutoff, Cutoff Modulation, Resonance, Width, Width Modulation, Keytrack

Envelopes

• Count: 2 independent envelopes
• Type: ADSR + Sustain Fall stage
• Features:
  • ENV 1 normalized to amplitude
  • Sustain Fall parameter for key-down shaping
  • Repeat function for looping envelopes
  • Velocity positive and negative control
  • Legato mode per envelope
  • East Coast design with cycling capability

LFOs

• Count: 2 LFOs
• Waveshapes: 4 per LFO
• Features:
  • Fade In/Fade Out parameter (bipolar)
  • Sync capability
  • Rate control
  • Key trigger modes

Modulation

• Modulation Matrix: Visual 3x6 grid system
  • Control (6 destination choices)
  • Source (6 effector choices from envelopes/LFOs)
  • Scale (scaling control options)
• Additional Modulation: Ring modulation, Oscillator drift

Effects

• Reverb: Schroeder-type (mono)
  • Time control
  • Level control
  • High Pass Filter
  • Low Pass Filter
• Chorus: 4 algorithm types
  • Level control
  • Type selection
• Voice Spread: Stereo positioning control

Keyboard & Performance

• Keys: 37 full-size, semi-weighted, velocity-sensitive
• Aftertouch: Channel aftertouch
• Octave Shift: Available
• Joystick: Multi-function control
  • Pitch bend (left/right)
  • Performable vibrato
  • Latching hold mode (down position)

Arpeggiator

• Types: 6 modes (Up, Down, Up/Down 1, Up/Down 2, Played, Random)
• Sync Rates: 2nds to 32nds
• Features:
  • Tap tempo button
  • Swing (positive and negative)
  • Auto clock sync (MIDI/USB-MIDI detection)
  • Latch via joystick hold
  • 6 octave range
• Tempo Control: Dedicated tempo control

Memory & Presets

• Patches: 200 total (all in RAM, overwriteable)
  • Bank A: 100 factory presets (protectable)
  • Bank B: 100 user presets
• Patch Management:
  • Instant access via dual column button layout (2 banks × 10 groups × 10 patches)
  • Compare function
  • Initialize patch function
  • Undo function (including save steps)

Connectivity

• MIDI: IN, OUT, THRU (5-pin DIN)
• USB: USB-C port
• Audio Outputs: Stereo 1/4" line outs (L/Mono, R)
• Headphones: Stereo 1/4" output
• Pedals:
  • Sustain pedal input (switch)
  • Expression pedal input (continuous)
• Power: DC 9V input with master power switch

Additional Features

• Glide: Amount control with auto-glide mode
• Master Controls: Tune, Volume
• Duophonic Modes:
  • Standard duo mode
  • Duo mode with simple filter
  • Pan control for duophonic voicing
• Visual Feedback:
  • Voice activity LEDs (2)
  • Keyboard activity LED
• Mixer: Three-stage mixing (OSC1+OSC2, OSCs+Noise, Final+Ring Mod)
• Noise Generator: Adjustable density

Physical Specifications

• Dimensions: 620 × 320 × 110 mm
• Weight: 5.3 kg
• Construction: Matte-black metal and plastic enclosure
• Side Panels: Magnetic snap-on/off design

Included Accessories

• Power supply (9V 600mA)
• USB-C cable
• Getting Started Guide