Fancyyyyy — K-Accumulator Digital Complex Oscillator

• Manual PDF

Manual PDF

K-ACCUMULATOR Cheat Sheet

What it is

A complex digital oscillator voice built around: - Main OSC with stereo sine/cosine outputs - Mod oscillator for PM / harmonic relationships - UFG = function generator / oscillator / modulation source - Δ–∑ = stepped/smoothed pattern generator - Root pitch system tying sections together

Best mindset: start from Centre (pure sine/cosine), then add Shift / Depth / Shape / Stretch / Damped-Pulsar one at a time.

Fast Start

Centre state

To get back to a clean reference sound: - Center all attenuverters - Damped/Pulsar fully CCW - Stretch fully CCW - Shift / Depth / Shape fully CCW

This always gives pure sine + cosine at the main outputs.

First moves

1. Patch Sine out and Cosine out to L/R mixer inputs.
2. Use Freq. to set oscillator pitch.
3. Raise Shift for blended harmonic frequency shifting.
4. Raise Depth for self-feedback phase-mod distortion.
5. Raise Shape for harmonic wavefolding.
6. Turn Mod Detune to animate the folder.
7. Add Stretch to shift generated harmonics while keeping the fundamental fixed.
8. Raise a waveshaper CV attenuverter to let UFG or Δ–∑ modulate it.
9. Raise Damped/Pulsar for sync + AM from the UFG.
10. Use 1V/TZ attenuverter to bring in Δ–∑ pitch motion.

Core Concepts

Root system

The Root section sets the tuning reference for: - OSC - UFG - Mod oscillator

You can quantize Root to: - 12-TET - Just Intonation

Morph system

The Morph encoder moves through a matrix of waveshaping topologies, not separate engines.

Good beginner route: stay on the left-hand path: - FMNT → FBPM → 2OP → XPM → Asym This path keeps control meanings more consistent.

OSC control meanings in most modes

• Shift = harmonic frequency shifting
• Depth = phase modulation / PM amount
• Shape = wavefolding

Best Practical Patches

1. Pure stereo oscillator

• Go to Centre
• Patch Sine + Cosine
• Tune with Freq.
• Optional: route Root to OSC for quantized pitch

2. Animated harmonic tone

• Start at Centre
• Raise Shift
• Raise Shape
• Turn Mod Detune
• Add a little Stretch

3. West-coast-ish complex tone

• Morph to 2OP or XPM
• Raise Depth
• Set Mod Order near center or higher
• Use Harmonic for ratio
• Fine-tune with Detune

4. Percussive / pulsar voice

• Raise Damped/Pulsar
• Set UFG Time to sub-audio
• Trigger UFG
• Shape UFG with Skew and Shape
• Patch OSC outputs to LPG/VCA/filter as desired

5. Quantized melodic sequence

• Route Root to OSC
• Enable Scale
• Use Δ–∑ into OSC via normalled modulation or external patching
• Use Chance / Length / Smooth to evolve sequence
• Turn on Q.Trig for threshold-triggered UFG behavior

6. External audio tracking

• Patch external waveform into Ext. Sync/Track
• Set button to Track
• K-ACCUMULATOR follows pitch and outputs shaped sine/cosine
• Works well for square waves, weird but recognizable with voice/material

Morph Modes Reference

Poles

• FMNT (green): formant-like AM + PM
• Asym (yellow): asymmetric PM/AM, granular pulse-train-like spectra

Left-hand path

• FBPM (green): self-feedback PM, sine-to-saw style distortion
• 2OP (yellow): Mod oscillator PMs OSC
• XPM (red): cross-phase modulation feedback

Right-hand path

• FBPM2 (green): chaotic self-feedback / subharmonic latching
• 2OP2 (yellow): separated self-mod vs Mod PM
• XPM2 (red): fully separated XPM controls

Color meaning

• Green = self-feedback PM only
• Yellow = Mod oscillator PM added
• Red = cross-feedback between oscillators

Controls Reference

1. Root Section

Knobs / Buttons

• Root knob
• Sets root frequency
• Mode selected by CRS/FIN/OCT button
• CRS/FIN/OCT button
• Cycles:
  • coarse
  • fine
  • octave
• Soft-pickup behavior
• Scale knob
• Selects one of 21 scales in current tuning system
• TET/JI button
• Toggles 12-TET / Just Intonation
• Root Send button
• Routes Root to:
  • OSC only
  • OSC + UFG
  • UFG only
  • neither

Jack

• 1V input
• 1V/Oct calibrated input for Root pitch
• Voltage range: not stated in quick-start manual

2. OSC Section

Outputs

• Main Sine output
• Waveshaped sine output
• Intended as stereo pair with cosine
• Output voltage range: not stated in quick-start manual
• Main Cosine output
• Waveshaped cosine output
• Output voltage range: not stated in quick-start manual

Knobs / Buttons

• Freq.
• Main oscillator frequency
• Q.Trig button
• Sends trigger to UFG when oscillator crosses quantizer thresholds
• Requires Root tracking + scale
• Stretch
• Harmonic stretching / harmonic-only shifting
• Damped/Pulsar
• Amount of damped sync + AM from UFG or external source
• Ext. Sync/Track button
• Cycles:
  • Sync
  • Track
  • Off
• Shift
• Waveshaping control
• Depth
• Waveshaping control
• Shape
• Waveshaping control
• Morph encoder
• Selects morph position
• Press = coarse/fine
• Double-press = snap to nearest position

Jacks

• Ext. Sync/Track input
• External sync source or pitch tracking source
• Voltage/audio range: not stated
• TZPM input
• External AC-coupled through-zero phase modulation
• Voltage range: not stated
• 1V/TZ input
• Auto-detecting pitch CV / through-zero FM input
• Stepped/slower CV treated as DC-coupled 1V/Oct
• Audio-rate treated as AC-coupled TZFM
• Voltage range: not stated
• Shift CV input
• CV for Shift
• Normalled from UFG or Δ–∑
• Voltage range: not stated
• Depth CV input
• CV for Depth
• Normalled from UFG or Δ–∑
• Voltage range: not stated
• Shape CV input
• CV for Shape
• Normalled from UFG or Δ–∑
• Voltage range: not stated
• Morph CV input
• CV for morph position
• Voltage range: not stated
• Damped/Pulsar CV input
• CV over damped sync/pulsar amount
• Voltage range: not stated

Attenuverters / mini-controls

• 1V/TZ attenuverter
• Shift attenuverter
• Depth attenuverter
• Shape attenuverter
• Morph CV attenuverter
• These have:
• midpoint deadzone
• exponential response
• Bottom-row source select buttons:
• LED lit = Δ–∑ normalled
• LED unlit = UFG normalled
• cable inserted overrides normalization

3. Mod Section

Knobs / Buttons

• Harmonic
• Sets Mod oscillator ratio/offset relative to tracked source
• Order
• Sets Harmonic behavior:
  • min = free pitch offset
  • center = blended harmonics above, free below
  • CW = odd-harmonic emphasis
  • CCW = even-harmonic emphasis
  • max = quantized to current scale / integer ratios
• Detune
• Detunes Mod from tracked frequency
• Also animates main harmonic folder behavior
• OSC/UFG button
• Selects Mod tracking source:
  • OSC
  • UFG
  • none lit = Root

Jack

• HMX/TZ CV input
• CV for Harmonic / TZ-related behavior
• Tracks 1V/Oct in free-pitch mode at full attenuverter
• Voltage range: not stated

Attenuverter

• HMX/TZ attenuverter

Outputs

• No dedicated Mod audio output shown in quick-start

4. UFG Section

Outputs

• Function output
• Anti-aliased function waveform
• Output voltage range: not stated
• Gate output
• Gate/pulse output, pulse width set by Skew
• Output voltage range: not stated

Knobs / Switches / Buttons

• Loop/Trig 3-position switch
• Up = toggle looping
• Middle = single-shot triggered externally
• Down = momentary manual trigger
• Time
• UFG rate/frequency
• Skew
• Rise/fall asymmetry and gate pulse width
• Shape
• Morphs linear / sine / exponential / raised cosine
• Type button
• 4 trigger response modes:
  • hard sync with subharmonic locking
  • sync reversal
  • sustain + hard sync
  • sustain + sync reversal

Jacks

• Time CV input
• 1V/Oct tracking
• Unpatched: random walk available through attenuverter
• Voltage range: not stated
• Skew CV input
• Unpatched: Δ–∑ normalled here
• Voltage range: not stated
• 1V input
• 1V/Oct input for UFG frequency
• Voltage range: not stated
• TZFM input
• AC-coupled through-zero FM
• Voltage range: not stated
• Trig input
• External trigger/gate input across full frequency range
• Voltage range: not stated

Attenuverters

• Time CV attenuverter
• Skew CV attenuverter

5. Δ–∑ Section

Output

• Δ–∑ output
• Stepped or smoothed pattern CV
• Good for pitch, PM, TZFM, or modulation
• Output voltage range: not stated

Knobs / Switch

• Chance
• Probability of new values entering sequence
• min = locked loop
• max = fully renewed
• Length
• Zooms pattern length from 2–16 steps
• center deadzone = 8 steps
• Smooth
• Glide/filter amount
• Pattern switch
• Right = enter new value at current step
• Left = restore previous value
• Hold right = overwrite pattern
• Hold left = double-length pattern

Jack

• Clock input
• External clock breaks UFG normalization
• Voltage range: not stated

Jack Summary

Outputs

Inputs

Control Summary

Knobs

• Root
• Scale
• Freq.
• Stretch
• Damped/Pulsar
• Shift
• Depth
• Shape
• Morph
• Harmonic
• Order
• Detune
• Time
• Skew
• UFG Shape
• Chance
• Length
• Smooth

Attenuverters / mini-pots

• Root 1V attenuverter
• OSC 1V/TZ attenuverter
• Shift attenuverter
• Depth attenuverter
• Shape attenuverter
• Morph CV attenuverter
• Mod HMX/TZ attenuverter
• UFG Time CV attenuverter
• UFG Skew CV attenuverter

Buttons / push functions

• CRS/FIN/OCT
• TET/JI
• Root Send
• Q.Trig
• Ext. Sync/Track
• Morph encoder press
• Morph encoder double-press
• OSC/UFG (Mod source)
• UFG Type

Switches / toggles

• UFG Loop/Trig 3-position switch
• Δ–∑ Pattern momentary switch

Important Behaviors / Gotchas

• Centre is your reset point. Learn it.
• Many OSC CV inputs are internally normalled to UFG or Δ–∑.
• OSC bottom-row source buttons:
• LED lit = Δ–∑
• LED off = UFG
• 1V/TZ input auto-detects slow CV vs audio-rate input.
• Stretch only works when waveshaping is active.
• Detune affects both Mod pitch relationship and folder animation feel.
• Q.Trig only works meaningfully when quantized Root tracking is active.
• Δ–∑ edits are non-destructive at minimum Chance.

Missing Technical Data

The quick-start manual does not specify actual voltage ranges for CV inputs or outputs. It only explicitly states: - some inputs are 1V/Oct calibrated - some are AC-coupled - some are through-zero - some are normalled internally

For exact voltage ranges, a full technical manual would be needed.

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