Tesseract Modular TUKRA - trigger sequencer with audio and midi

Hi all, would like to share something I’ve been working on for several months, it’s a trigger sequencer with audio and midi capabilities. The project is getting close to the release (this is the second prototype and the firmware is in a pretty advanced phase)

-64 patterns (with up to 64 steps each).
-64 parts (with up to 64 patterns).
-16 songs (with up to 64 parts).
-64 projects in the microSD card (with all the above each).
-Play mode (forward, backward, pendulum and random, all of them with or without step repeat) clock divider and length independent per track & pattern.
-Step value (can be used for modulation, to define the midi velocity, midi note & drum synth note or sample selection)
-Probability for step, gate and roll.
-Swing (aka shuffle).
-Micro grid edit (each step has 6 micro steps).
-Euclidean Rhythm Generator.
-8 internal LFOs.
-Ramifications (generative algorithm, adds from subtle to drastic variation but in a pretty coherent way).
-Drum synth (volume, decay, pitch, pitch envelope amount, noise level and noise decay).
-One shot sample player (internal & user banks).
-Mixer with volume, balance, reverb and bit crusher.
-Filter per channel with cutoff, resonance and filter type (which smoothly crossfades from LP to BP to HP)
-Modulation matrix for almost all parameters.
-Live view to perform solo, mute, fill, roll, invert, reverse and rotation in any track.
-Non destructive mode.
-4 CV inputs with offset pots (0 to +10v, -5v to +5v etc…)
-8 trigger outs, clock + reset in & out.
-Tempo internal, external or midi synch. Double and half tempo.
-Midi trs in & out (input is ‘either way’ for Korg or Arturia pinouts, output configurable with switches).
-USB host for midi controllers.

so this is more or less what it is, it has no oled screen and no sub-menus so all functions are accessible all the time…btw the 16 songs are not just ‘songs’ in the traditional sense, they are also 16 presets for the tempo, swing, mixer, drum synth and modulation settings.

Please express your opinions/suggestions/criticism/insults, thanks!


good grief. this is a beast

this spring I’m planning to add some tesseract to my rack, and this just made the list. Is the CV routable? what can it control? and I’m assuming this will be offered DIY format like your other stuff, right?

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the CV is one of the modulations sources available in the modulation matrix (there are also LFOs, midi CC with midi learn function - very easy to assign, random or the step value of any track), the amount of modulation is configurable (it can be positive or negative) and the pots can be used for manual control (so even if there is not CV present is fun to assign things there) or to set the voltage range for the inputs. The parameters that can actually be modulated are:

pattern Length
pattern Clock divider
pattern Euclidean number
pattern Euclidean rotation
Sample player volume
Drum volume
Drum decay
Drum pitch
Drum pitch envelope
Noise level
Noise decay
Track level (the sum of drum, noise and sample)
Reverb amount
Filter frequency
Filter resonance
Filter type
Bit crusher
the same modulation source (for example CV input) can be assigned to several parameters with different amounts, but each parameter can be modulated only by one source. In the mixer and drum synth views pressing shift will show how the parameters are being modulated…which is useful and fun to see.
there will be a DIY option for sure, not decided if it will be PCBA+panel or partial kit (with all led pipes, translucent shaft pots…)


I’ve been following you on IG and I saw that a while back. What a beast indeed! It looks so welcoming to play. I hope it’s a big success for you - your designs are always enticing but this definitely stands out in terms of complexity.


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thx dude, for sure this is the most ambitious/complex design I’ve ever try to do, but also it has turn in to the most original/personal one


Nice! :+1:

That’s a lot of functionality! Despite the lack of a menu it might still be a bit much for a user to handle? That’s a lot of icons to remember.

Regarding the listed functionality:
How does the step value for pitch work? Is there a quantizer? And how does it work? Using the buttons or the knob/encoder top left?
And what do you mean with note repeat? That you can set per step how many times that step repeats?

For me some videos would probably help with understanding what it can do and how it works. Might be a bit too early for that though?

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Pronto @M4ngu !
20 si si si

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I love your modules dude, I have 3 in my rack already and looking forward to adding this beast to it.

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Hey Mangu,

TUKRA looks awesome! I’m definitely interested, since it looks it could do double duty with its own sounds and also drive a DRM-1 (-:

Here are my initial comments

  • Incidentally, can it do pitched one-shot samples?
  • Do all the icons in the grid represent some feature?
  • Presumably the per-step velocity is represented by per step led intensity. Is this correct?
  • It would be great to be able to save to or load from a midi file and to keep them stored on the module which is accessible as a drive… (killer feature request)


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the use it’s easy, if you just want to make patterns and go, if you want to make complex things using all the generative and modulation tools it won’t be so instant for sure, but neither too complex IMO.

Many icons, but organised in rows like: bottom has the mixer ones, next row drum synth, next performance actions etc. I think it helps, indeed organizing all the functions/parameters has been harder than I expected …and still making some small changes.

The step value goes from 0 to 127, when the option ‘step value 2 midi note’ is active on a track, the outgoing midi note will be that value, 69 will correspond to a midi note A4 and the frequency of the drum would be 440Hz, so yes, with that option there is a quantizer for the drum frequency but chromatic.

step value is set with the encoder (to single steps, a selection of them or all the track) you can easy make ramps, randomize, copy…) it can be edited also in a view where the step values are displayed like columns (so like editing the velocity in a daw)
and in real time recording each row of the button grid is a track, and will play a note with a different step value depending on the column you click, left one smaller, right higher…

With step repeat I mean that if the clock divider of a track is 3, the step can be repeated 3 times of just play once during those 3 pulses, actually different step repeat times can be achieved by modulating the clock divider but there is not a parameter dedicated to set the repeats for each step …maybe is something to implement,

for sure there will be a video as soon as the unit is ready for production. Long text sorry xD


The sample player is pretty basic, it does not have pitch control, so is a simple ‘one shot’ sample player, but the latency is good, and layering the sample with the drum synth & noise plus processing them with a filter and the bit crusher gives a nice amount of possibilities.

Yes all icons are something, a function or a parameter.

The step velocity is represented by colors in the step value edit view (goes gradually from blue to red) in other edit views, the step value won’t have any representation, for example in the roll probability is that parameter the one represented by colors.

about midi files…I would like to add a feature which is to assign a midi file form the microSD to a song and play it synched, but those are just ideas I have…I’ve found a midi file parse code but that’s all, haven’t tested it etc

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are there any videos planned for those of use who learn by seeing rather than reading? this looks fantastic and very capable, would love to see a rundown and hear some of the samples.

I’ll try to make better videos…
here’s one with TUKRA playing the same pattern and using the songs as presets for drums, mixer and modulation setup

and here’s one with basic edit functions (copy, past, randomise, clear)
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My friend Antón made an introduction video:

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Some audio examples