XILS-lab PolyKB III

XILS-lab · Virtual Instrument · VST / AU / AAX
ACTIVETALISMAN ORIGIN
PolyKB III is the instrument that unlocked So Blue Above You — the first real TALISMAN writing session, April 17, 2026. Key of G, waltz feel, the chorus arrived complete in a single afternoon.

Overview

The PolyKB III is a virtual instrument based on the architecture of a rare vintage polyphonic synthesizer featuring continuous waveform morphing — a revolutionary feature that allows oscillator waveforms to transition smoothly from triangle through saw to pulse in real time, with full modulation of the morphing parameter. The result is a palette of evolving, organic textures unavailable in standard subtractive synthesis.

Developer
XILS-lab (Xavier Oudin)
Architecture
3 morphing oscillators, dual 4-pole filters, 3 envelopes, 4 modulation matrices
Polyphony
Up to 16 voices
Formats
VST, AU, AAX (Mac OSX 10.7+)
Authorization
eLicenser USB dongle or iLok
Cubase Location
Instrument tracks — Writing Session template

Oscillators

Three aliasing-free oscillators with continuous waveform morphing. The morphing parameter is fully modulatable — this is the defining characteristic of the PolyKB architecture.

Waveform Morphing Path

The WAVEFORM knob sweeps continuously through the following shapes in order:

Triangle → Saw → Double Saw → Square → Pulse (narrow)

Every intermediate position is a unique waveform. Modulating this parameter at audio or LFO rates produces timbral evolution that cannot be replicated by standard oscillator designs.

ParameterFunction
FREQUENCYTuning in semitone steps (left mouse button) or fine Hz (right mouse button)
WAVEFORMContinuous morphing from triangle to narrow pulse — fully modulatable
VOLUME (Osc 2 & 3)Continuous output level knob
VOLUME (Osc 1)Three fixed levels via switches: 1/3, 2/3, 1 (both switches off = mute)

Oscillator 2 & 3 Special Features

SwitchFunction
SYNCHard sync Osc 2 to Osc 1 — Osc 1 forces Osc 2 cycle restart
KB (Key Off)Disconnects Osc 2 from keyboard — pitch stays fixed regardless of note played
LOW (Osc 2 only)Drops Osc 2 to sub-audio LFO rates. Pitch tracks keyboard unless KB is also on — creates a keyboard-rate-dependent LFO
TUNSlight detune of VCO2 relative to VCO1 — increases phasing and width

Noise Oscillator

ParameterFunction
Noise VOLUMEThree fixed levels: 1/3, 2/3, 1 (both switches off = mute)
[White Noise] labelClick to toggle between White and Pink noise types
Noise Filter LEDBand Limited Noise mode — removes harsh high frequency content

Filters

Two independent dynamic 4-pole self-oscillating filters — each switchable between Low Pass, High Pass, and Band Pass modes. Each filter has its own input selector, and a mixer knob sets their relative blend. All audio routing combinations are possible: parallel, serial, or mixed.

ParameterFunction
FREQUENCYFilter cutoff frequency
RESONANCEResonance / Q factor. At maximum, filter self-oscillates — outputs sine wave even with all oscillators muted
KEYB CTRLKeyboard follow amount applied to cutoff
ADSR2 CTRLAmount of Envelope 2 (Filter EG) applied to cutoff
DRV PREOverdrive emulation — subtle low-end enhancement to full saturation depending on level
[DRV PRE/POST]Click label to toggle overdrive position before or after filter stage
Each filter has independent input selector switches — Osc 1, Osc 2, Osc 3, and Noise are independent inputs to each filter. The mixer knob blends Filter 1 and Filter 2 outputs.

Envelopes

Three ADSR envelope generators. EG1 is hardwired to VCA (amplitude). EG2 is hardwired to Filter 1 cutoff. All three are available as modulation sources in the matrix sections.

ParameterFunction
ATTACKTime for output to rise from zero to maximum
DECAYTime for output to fall to sustain level
SUSTAINLevel held while note is gated
RELEASETime for output to fall to zero after note off
KB (Key Track)Keyboard follow applied to EG parameters — higher notes = shorter attack
LO (Loop)EG 2 or 3 cycles continuously Attack→Release while note is held, bypassing Sustain
MUL (Multiplier)Multiplies all ADSR times by 2, 3, or 4 — essential for long pad attacks and releases

LFOs

Two multi-waveform LFOs with MIDI sync, polyphonic and monophonic modes, delay, and fade-in. Multiple waveforms can be selected simultaneously to build complex LFO shapes.

ParameterFunction
RATELFO frequency
Waveform switchesMultiple waveforms can be active simultaneously — triangle, sine, square, noise (S&H at LFO rate). Click sine/triangle label to swap between the two.
DELAYTime between note ON and start of LFO fade-in
FADETime for LFO output to rise from zero to full level after delay
S (Sync)Locks LFO rate to host tempo — rate displays in musical notation when active
Tip: Combining multiple LFO waveforms avoids the mechanical, repetitive feel of a single-waveform LFO. For subtle movement and breath in sustained sounds, stack sine + small amount of noise.

Modulation

Four independent modulation matrices — one of the most comprehensive modulation architectures in any virtual synthesizer.

1 — Hardwired Matrix (Main Switch Matrix)

Five fixed sources connect to predefined destinations via switches. This is the original vintage PolyKB matrix. Switches have three states: Green LED = positive modulation, Red LED = negative modulation, no LED = path disconnected.

SourceAvailable Destinations
LFO 1Pitch VCO 1/2/3, Waveform morphing VCO 1/2/3, Filter 1&2 Cutoff
Noise / LFO 2Pitch VCO 1/2/3, Waveform morphing VCO 1/2/3, Filter 1&2 Cutoff
ADSR 2Pitch VCO 1/2/3, Waveform morphing VCO 1/2/3, Filter 2 Cutoff (not Filter 1 — already hardwired)
VCO 2Pitch VCO 1&3, Waveform morphing VCO 1&3, Filter 1&2 Cutoff
VelocityVCA, Filter 1&2 Cutoff, Envelope Attack, Envelope Decay/Release
WHEEL switch on any row: when active, the modulation amount for that row is controlled by the Mod Wheel rather than being fixed.

2 — Dropdown Matrix (User Mod Panel)

Two freely assignable sources each modulate up to four selectable destinations. Sources and destinations chosen from comprehensive drop-down menus. Positive/negative modulation via green/red LED switches.

Sources include: ADSR 1/2/3, Velocity, Aftertouch, LFO 1&2 (poly or mono), Mod Wheel, Sequencer Pitch, Sequencer Velocity.

LFO Mono vs. Poly: LFO 1&2 M sources run identically across all voices. Standard LFO 1&2 sources trigger a fresh LFO instance per voice. Combining both in the same patch creates layered modulation depth.

3 — Velocity Assignation Panel

ControlFunction
VCA [+] / [x]Additive or multiplicative velocity applied to output level
Pressure ONPolyphonic aftertouch adds to Mod Wheel level
ATTKVelocity modulates envelope attack times
DECVelocity modulates decay and release times
VCF 1&2Velocity modulates Filter 1 and 2 cutoff
The MAIN velocity knob in the Keyb/Arp panel is a global velocity scale for all matrix assignments. If set to zero, no velocity modulation occurs anywhere regardless of other settings.

4 — VOICEXY Matrix

An XY pad where each voice is represented as a movable point. Voice position on the X and Y axes independently modulates two assignable destinations. Amount controlled by four corner knobs. In Polyphonic Circular mode, voices are dynamically reassigned as notes are played — creating unpredictable, evolving modulation patterns from arpeggios and chord progressions. See VOICEXY section below for full detail.

Arpeggiator & Sequencer

Arpeggiator

ControlFunction
ONEnable / disable arpeggiator
Up / Down / Up-DownNote play order. No mode selected = random order.
OctCycle through additional octave before restart
PolyPolyphonic mode — plays chords per a user-defined sequence of transpositions
Octave NumberNumber of octaves when Oct is active
Playing ModeFree (immediate update), After Each Note, After Each Cycle
SWINGSwing amount. Full right = no swing. 66% = typical jazz swing.
GATENote hold time, from zero to full clock period
Chord SequencesTransposition values for polyphonic mode (0–12, up to 32 steps, space/comma separated)
M.SYNCSync arpeggiator clock to host tempo

Polyphonic Sequencer

128-step polyphonic sequencer with up to 8 independent voice sequences. Records pitch and velocity. Sequencer presets are stored and recalled independently from instrument presets.

ControlFunction
Voices SelectSelect which voices are recorded or played
VCE DELDelete all steps for selected voice (confirmation required)
STP DELDelete current step for selected voice (no confirmation)
TRG (Triggered)Sequencer starts only while a note is held — stops on note release
TUN (Tuned)Transposes sequence to lowest note played on keyboard
Step/RunStep-by-step recording or playback mode
Max/Current displayLeft-click to increase max steps, right-click to decrease. Click current step to reposition.

Sequencer Display Module

Three zoom modes: Zoom 1 = full range (useful for parameter modulation), Zoom 2 = 4 octaves, Zoom 3 = 2 octaves. Left-click to add or modify a step, right-click to erase. Check Velocity box to display/edit velocity instead of pitch. +/- rotate buttons shift sequence left or right by one step.

Sync: To fully sync the arpeggiator and sequencer together, enable MIDI sync on both AND enable the sequencer Trigger switch. This resets the sequencer clock each time a note is played, locking the two modules in phase.

SPACEXY & VOICEXY

SPACEXY — Dynamic Stereo Enhancer

An XY room simulation that positions each voice in a stereo space relative to two virtual cardioid microphones. Voice positions are independently movable. Dynamic modes animate the positions in real time.

ControlFunction
WIDTHStereo field width. Wide setting introduces subtle time differences between voices and microphones — can add groove to sequences.
Mic knobOrients the cardioid pickup pattern of the two virtual microphones
Init Pos.Preset voice placement: Random Wide or Random Tiny
DYN modesAquarium (random drift), Magnet (voices exchange positions), Path (follow recorded paths)
SPEEDSpeed of dynamic movement
AMOUNTDepth of dynamic movement
SPACEXY ON switchGlobal enable / disable in main panel

VOICEXY — Polyphonic Modulation Matrix

Each voice is a movable point on an XY pad. X and Y axis positions independently modulate two assignable destinations. In Polyphonic Circular mode, each incoming note activates the next point — creating a dynamic, evolving modulation pattern driven by performance.

ControlFunction
Four corner knobsModulation amount for X+, X-, Y+, Y- axes independently
Destination menusSame destinations as Dropdown Matrix — any parameter
Init Pos.Preset voice positions: Random Wide or Random Tiny
DYN / PATHVoices follow recorded paths. Right-click and draw path. Double-click to delete.
Red circle → GreenA voice turns green when actively sounding — monitor voice assignment in real time
VOICEXY with Polyphonic Circular mode and an arpeggio or sequencer produces fully predictable, repeating modulation patterns. With free keyboard playing it produces organic, unpredictable results. Both modes are musically useful.

Effects

ModuleParameters
DelayDry/Wet, Time (L/R independent), Feedback (L/R independent), Sync to host tempo
ChorusDry/Wet, Rate, Amount, Type (3 algorithms)
PhaserDry/Wet, Speed, Amount (sweep depth), Freq (center frequency), Res (feedback), Stereo (L/R phase offset)
EQTwo shelf filters (High/Low). Each: Freq, Res, Gain (centered knob — CW boost, CCW cut), ON LED. Both EQ ON LEDs and the main EQ switch must be active.
ReverbDelay (pre-delay), Level, Damp (HF rolloff), Type (Large/Medium/Small), HP (110Hz high-pass on input)
Dropdown Modulation tip: Slight modulation of Chorus or Phaser rate adds subtle movement to sustained sounds. Modulating Delay time produces spring reverb-like ambiance. Both are excellent for TALISMAN-style evolving textures.

Keyboard & Output Settings

ParameterFunction
OUTPUTSMaster output level
TUNEGlobal pitch offset
SPACEXY ONEnable / disable SPACEXY stereo enhancement
BENDERPitch bend range in semitones
[GLIDE]Glide (continuous) or Glissendo (semitone steps). Polyphonic glide available — each voice glides independently.
VELOCITYGlobal velocity scaling for all matrix modulations
AFTERPolyphonic aftertouch level for modulation
DRIFTPer-voice random detuning and parameter variation — emulates component tolerances in analog hardware. Full left = all voices identical.
NBR VCESAvailable voice count (1–16). Affects SPACEXY and VOICEXY behavior. Reduce to limit CPU with long releases.
UnisonNumber of voices triggered per note. Set NBR VCES to a multiple of Unison setting for correct behavior.
Play modePOLY circular (voices assigned in rotation), POLY reset (always from voice 1), MONO low/high/last priority

Preset Management

The PolyKB III has two independent preset systems: Global presets (instrument sounds) and Sequencer presets (sequences stored separately). Both use the same multi-criteria browser.

FunctionNotes
Sort criteriaAuthor, Type (category), Style (genre), Feeling (character), Project, Bank
Save / Save AsFactory presets are locked — must use Save As to store edits. User presets can be overwritten with Save.
A/B ComparisonStore two independent settings and toggle between them. Copy A→B or B→A with arrow buttons.
Export Preset.epkb format for individual preset backup
Export BankCross-platform bank export (Mac and PC compatible)
Favorite / HiddenTag presets as Favorite (show only favorites) or Hidden (remove from list)
* indicatorAsterisk after preset name = unsaved edits exist
Sequencer presets are managed completely separately from instrument presets. Opening the Sequencer Preset Manager while in the Global manager will show only global presets and vice versa.

Key Tips & Workflow Notes

TopicNote
Waveform morphing as PWMSmall WAVEFORM modulation amount on Square wave ≈ classic pulse width modulation. Larger amounts = dramatic timbral morphing.
Osc 2 LOW + VCO2 matrix rowUsing Osc 2 in LOW mode as a modulation source via the VCO2 matrix row creates a keyboard-tracking LFO — higher notes produce faster modulation.
Envelope LOOPEG2 or EG3 in Loop mode with short A/D creates a rhythmic timbral pulse while a note is held.
LFO multi-waveformStacking multiple LFO waveforms avoids mechanical repetition. Sine + noise = natural breath.
Velocity / VCAFor maximum dynamic range: MAIN velocity fully CW, VCA switch green, mode set to [x] (multiplicative).
SPACEXY WIDTHWide setting introduces subtle timing differences — can add micro-groove to sequenced parts.
Voices & Sequencer prioritySequencer voices always have priority. If NBR VCES = 1 and sequencer uses 3 voices, keyboard gets no voices. Set NBR VCES high enough to accommodate both.
Delay time modulationModulating delay time in the Dropdown Matrix produces spring reverb-like ambiance effects.
Filter self-oscillationResonance at maximum produces a pure sine tone with no oscillator input needed — useful as a pitched effect or tone source.