Timo Rozendal Filler Drum Variation Module

Filler is a hands-on Eurorack drum variation module that listens to your drum triggers, learns the rhythm, and adds fills, variations, transformations, and accents in sync with your clock.
Patch in your drum triggers, let Filler listen for a few bars, then press Fill to drop in a one-bar fill, variation, roll, mute, or database-matched transition. It is made for live performance: tight when you want it locked to the bar, immediate when you want to throw in a fill right now.

It comes in two versions:
- Full DIY kit (with all the smd assembled) , price 160 euro (this listing)
- Built module, price 250 euro (other listing)


6 trigger inputs + 7 trigger outputs
Bass drum, snare, closed hat, open hat, perc 1, perc 2, plus an automatic cymbal/crash output when a fill ends.
Learns your rhythm
Filler listens to the incoming drum pattern and uses it to create musical fills and variations that stay connected to what is already playing.
One-bar fills on command
Press Fill and Filler inserts a fill at the next bar boundary, then returns to the original rhythm.
Direct mode
Need something spontaneous? Direct mode starts the fill immediately from the current position in the bar.
Built-in fill library
333 curated fill patterns organized in 41 banks, including classic, rock, metal, jazz, country, rolls, fast fills, and more.
Multiple fill modes
Mute, Built In, Automatch, Variation, Euclidean, and Roll modes give you different ways to create transitions and breaks.
Always-on drummer layer
A second layer continuously transforms the incoming rhythm with ghost hits, slicing, humanization, probability, stutters, negative-space patterns, phase shifts, and Markov-generated variations.
Clock-synced, shuffle-friendly
Locks to an external 16th-note clock and handles swung or shuffled clocks.
CV input + CV output
Route CV to the Fill Param or Drummer amount, and use the synchronized CV envelope output to control filters, VCAs, effects, or other modulation destinations.


Mute - silence the drum pattern for dramatic stops
Built In - choose from the 333 internal fills
Automatch - finds fills that match your incoming rhythm
Variation - reshapes the current pattern into a related fill
Euclidean - generates algorithmic rhythmic fills
Roll - creates roll and buzz-style fills


Ghost/Displace - adds ghost hits and timing shifts
Slicer - chops and rearranges the pattern
Groove Humanize - makes rigid rhythms feel more alive
Probability - thins and varies hits
Stutter - repeats slices for glitchy effects
Neg-Space - fills gaps in the snare pattern
Phase-Cascade - shifts channels apart in Reich-style phases
Markov - learns your rhythm and generates statistical variations


Patch in your drum triggers
Wait 2-3 bars while Filler learns the pattern
Press Fill for a synced transition
Use Direct mode for instant mid-bar fills
Turn Drummer for continuous variation
Send CV in to animate fill or drummer intensity
Use the CV envelope output to make the rest of your patch react
Simple to patch, deep once you start playing with it.


Width: 14HP
Depth: 30mm
Power: +12V 75mA / -12V 5mA / 5V 0mA
Trigger inputs: 6
Trigger outputs: 7
Clock: external, 1 pulse per 16th note
CV input: 0-5V
CV output: 0-6.5V fill envelope
Controls: rotary encoder with push, 4 buttons, 2 knobs, OLED display