MarkovPerc
A first-order Markov chain rhythmic generator — the percussive sibling to MarkoV. Instead of scale degrees, the states are hit types: rests, plain hits, accented hits, flams, and ratchets. On each clock, the chain chooses the next hit type based on weighted probabilities from the current state, creating a drummer that develops evolving rhythmic patterns with internal memory and stylistic consistency.
I/O
| 1/3 | 2/4 | |
|---|---|---|
| TRIG | Clock — advance to next hit state | Reset — short press returns to seed state; long press sets a new random seed |
| CV INs | Chaos offset — adds to the encoder-set Chaos baseline | Density — biases toward hits vs. rests (positive voltage = more hits) |
| OUTs | Trigger — fires sub-triggers for ratchets and flams within the beat | Accent CV — 0–5V representing the accent intensity of each individual hit |
Output A fires multiple pulses per clock for ratchets (2–4 evenly spaced) and flams (a soft grace note followed by the main hit). Output B tracks the accent of the most recent sub-trigger and holds until the trigger length expires.
UI Parameters
Turn the encoder to move between parameters. Click to enter edit mode, click again to lock.
Aux button immediately resets to the seed state — useful in performance to return to a known rhythmic feel without interrupting the clock.
| Display | Parameter | Range | Notes |
|---|---|---|---|
| S / T / J / P | Style (Tendency Profile) | S, T, J, P | See profiles below |
| 0–100% | Chaos | 0–100% | Baseline chaos; CV In 1 adds on top |
The top line of the display shows the name of the currently-selected parameter.
Tendency Profiles
Each profile is an 8×8 transition matrix defining how likely each hit type is to follow any other. The row is the current state; the column is the next state. Higher numbers mean more likely. Weights range from 1 to 20; at 0% Chaos these weights dominate strongly.
S — Steady (Rock/Pop) Gravitates strongly toward plain hits and accented hits. Rests are brief — the machine quickly rebounds to playing. Flams appear as occasional ornaments. Ratchets are rare fills after dense passages. Produces a reliable, driving groove.
From Rst Hit AcH Flm AcF Rc2 Rc3 Rc4
REST: 2, 18, 12, 4, 2, 3, 1, 1
HIT: 4, 16, 10, 6, 2, 4, 1, 1
ACC_HIT: 4, 14, 10, 4, 4, 4, 2, 1
FLAM: 4, 16, 10, 4, 2, 5, 1, 1
ACC_FLAM: 6, 14, 10, 4, 2, 4, 2, 1
RATCHET_2: 8, 14, 8, 4, 2, 4, 1, 1
RATCHET_3:12, 12, 6, 2, 2, 4, 2, 2
RATCHET_4:14, 12, 6, 2, 2, 2, 2, 2
T — Syncopated (Funk/Latin) Rests are structurally meaningful pauses, not gaps to escape from. Flams are very common — from almost any state, a flam is a likely next event. Ratchet-2 serves as a common syncopation device. Higher overall energy than Steady, but with deliberate space built in.
From Rst Hit AcH Flm AcF Rc2 Rc3 Rc4
REST: 4, 10, 6, 12, 8, 10, 2, 1
HIT: 10, 6, 4, 14, 8, 10, 4, 2
ACC_HIT: 8, 8, 4, 12, 10, 8, 4, 2
FLAM: 8, 10, 4, 8, 8, 12, 4, 2
ACC_FLAM: 8, 8, 6, 10, 8, 10, 4, 2
RATCHET_2:12, 8, 4, 8, 6, 8, 4, 2
RATCHET_3:14, 8, 4, 6, 4, 6, 4, 2
RATCHET_4:16, 6, 4, 4, 4, 6, 4, 2
J — Jazz/Free Favours complexity: accented flams are the signature gesture, ratchets are common fills, and extended rests are followed by dense bursts of activity. The chain can self-reinforce into cascading ratchets (Ratchet-3 → Ratchet-4 → Ratchet-4…) before collapsing to a rest. Most unpredictable of the four profiles.
From Rst Hit AcH Flm AcF Rc2 Rc3 Rc4
REST: 4, 6, 4, 8, 14, 12, 8, 6
HIT: 6, 4, 4, 8, 12, 14, 10, 6
ACC_HIT: 4, 4, 4, 8, 14, 12, 10, 6
FLAM: 6, 6, 4, 6, 14, 12, 10, 6
ACC_FLAM: 4, 4, 4, 6, 12, 14, 12, 8
RATCHET_2: 8, 6, 4, 8, 10, 10, 12, 8
RATCHET_3:10, 4, 4, 6, 8, 8, 14, 10
RATCHET_4:12, 4, 4, 4, 6, 6, 12, 14
P — Sparse Strong pull back to rest from every state. Plain hits are the only reliable non-rest event; accented and ornamental hit types are rare and become increasingly unlikely the more active the current state. Produces very open, spacious patterns — long silences broken by single clean hits. Most useful as a sparse kick or occasional accent layer, or with Density CV to dynamically control busyness.
From Rst Hit AcH Flm AcF Rc2 Rc3 Rc4
REST: 12, 10, 2, 1, 1, 1, 1, 1
HIT: 18, 6, 2, 1, 1, 1, 1, 1
ACC_HIT: 16, 6, 4, 1, 1, 1, 1, 1
FLAM: 18, 4, 2, 2, 1, 1, 1, 1
ACC_FLAM: 18, 4, 2, 1, 2, 1, 1, 1
RATCHET_2:20, 4, 2, 1, 1, 2, 1, 1
RATCHET_3:20, 4, 2, 1, 1, 1, 1, 1
RATCHET_4:20, 4, 2, 1, 1, 1, 1, 1
Hit Types
| Display | State | Description |
|---|---|---|
Rst | REST | Silence — no trigger fired |
Hit | HIT | Single trigger, moderate accent (2V on Out B) |
AcH | ACC_HIT | Single trigger, full accent (5V on Out B) |
Flm | FLAM | Grace note (soft, immediate) + main hit (medium, slight delay) |
AcF | ACC_FLAM | Grace note (soft) + accented main hit (full accent) |
Rc2 | RATCHET_2 | 2 triggers evenly spaced across the clock period |
Rc3 | RATCHET_3 | 3 triggers evenly spaced |
Rc4 | RATCHET_4 | 4 triggers evenly spaced |
For ratchets, Output A fires at the start of the beat with a hard accent (4V), followed by softer repeats. For flams, the grace note fires immediately with a 1V accent; the main hit arrives ~1/8 of the clock period later.
Chaos
At 0% chaos the profile weights dominate — hit sequences are strongly shaped by the chosen style.
At 100% chaos all transition weights are equalised — any hit type is equally likely from any state, regardless of the current hit or the style. The profile has no effect.
CV In 1 adds to the encoder-set Chaos baseline, so you can set a floor with the encoder and modulate upward with voltage. Patching an LFO here creates evolving rhythmic density over time.
Density (CV In 2)
CV In 2 biases the chain toward hits or rests without changing the style:
- 0V — neutral, profile determines balance naturally
- Positive voltage — rest state becomes less likely, hit states more likely; pushes toward continuous playing
- Negative voltage — rest state more likely, hits less likely; creates sparser, more spacious patterns
Use Density to dynamically control how busy the pattern is in response to another part of your patch — for example, patching a slowly rising envelope during a build-up section.
Reset & Seed
Short press on Digital In 2 (or as a trigger): returns to the seed state — the same starting hit type every time. Use this to return to a known rhythmic feel at a section boundary.
Long press (hold Digital In 2 for ~1 second): picks a new random seed (never lands on REST) and jumps to it. That state becomes the new short-press reset point. The seed is saved with presets.
Aux button: instantly jumps to the current seed state without waiting for a clock edge — useful for quick resets mid-performance.
Display
The lower portion of the screen shows a scrolling history of the last 8 hit states, oldest on the left, newest on the right. Each state has a distinct visual glyph:
- Rest: tiny dot at the baseline
- Hit: single thin bar, full height
- Acc Hit: wide bar, full height
- Flam: short grace note bar + taller main hit bar
- Acc Flam: short grace note + tall wide main hit bar
- Ratchet-2: two medium bars
- Ratchet-3: three shorter bars
- Ratchet-4: four short closely-spaced bars
What is a Markov Chain?
A Markov chain is a mathematical model where the probability of the next event depends only on the current state — not on the history of how you got there. In MarkovPerc, each state is a hit type, and the transition matrix defines how likely you are to move to any other hit type from your current position.
The musical insight is that drumming styles have characteristic patterns of what follows what:
- Steady rock patterns tend to stay in motion with occasional ornaments
- Funk patterns use space deliberately and reach for flams
- Jazz patterns build tension through complexity and release through rest
- Sparse patterns return to silence as their default behaviour
By encoding these tendencies as probability weights, MarkovPerc generates rhythms that feel stylistically consistent without being deterministic or repetitive.
Tips
- Pair with a VCA or envelope: Output A’s trigger, combined with Output B’s accent voltage, can drive a velocity-sensitive VCA or envelope. The accent CV naturally shapes the dynamic contour of each hit.
- Use with a kick drum module: The structured rest/hit balance of the S profile produces reliable kick patterns that groove without becoming mechanical. Patch a second trigger-to-audio module into a different hemisphere channel for snare.
- Density sweep for builds: Patch a slow rising CV into CV In 2 to gradually push from sparse (rests) to dense (continuous hits) over a phrase or section.
- J profile for live improvisation: The Jazz profile’s tendency toward self-reinforcing ratchets creates natural peak moments. Use the Aux button to reset back to a simpler seed when the complexity gets too high.
- P profile + Density CV: At 0V Density the P profile is almost silent. Use Density to gradually introduce hits — the chain’s pull back to rest creates natural silences even at high Density values, giving you controllable sparseness rather than a fixed pattern.
- Pair MarkovPerc with MarkoV: Clock both from the same source. MarkovPerc drives a percussion voice while MarkoV generates a melody. The S/T/J profile names are intentionally parallel — matching the “mood” of both creates coherent ensemble textures.
- Long-press seed to change groove: Mid-performance, hold Digital In 2 to pick a new random seed and pivot to a different rhythmic starting point.
Credits
MarkovPerc by uglifruit.