This 8HP module contains three reverse sigmoid chaos circuits, these are the same as those used in 1U reverse Sigmoid and How’s the Serenity.
This version exists because not everybody has 1U and How’s the Serenity is quite large and more focused on very slow CV generation. This version is limited to 0805 capacitors to set the timing. Tayda sell 22uF caps and you could stack these to get to 44uF easily enough. Generally, a lot of fun can be had using 1uF, 470n and 220n caps.
The syncing between the stages works very nicely with this module as the frequency ranges are closer together than How’s the Serenity, so they have a more obvious effect upon each other.
Please note if you install caps less than 470n, the 62k on that section needs to be changed to 68k. This prevents the circuit locking into a periodic orbit after CV is applied.
The caps for each section must be the same. So you will see three pads marked C1, install the same value cap in all three.
The LEDs should be very bright to shine thru the panel, a low value for RL helps too, say 2k2 or 3k3 which you are installing elsewhere on the PCB anyway. The panel renders below do not show the LEDs but they are there.
"I'm still learning how to use this thing but here are some excerpts from a patch with Tinkle and FM OP via Product wavefolder both fed into the Spectrum Shaper."
via nonlinear circuits
"36 channel voltage controlled comb filter aka string filter.
This module has some history. In 2018, I was part of a team putting on a show with CellF at the Todays Art festival in Den Haag. I popped down to Rotterdam to visit Dennis (aka Mono-Poly) and his studio of vintage lab gear. Dennis had an incredible patch going centred around a Bruel & Kjaer 36 channel Spectrum Shaper. Listen to his album Testlab to hear how it sounds. I just knew I had to make something like it one day. This type of filter is often called a ‘String filter’, used to emulate stringed instruments tho don’t feel limited by that.
Fast forward to 2026, I read an AES paper by R. Burhans describing his 36 channel comb filter. It reminded me there were some designs in Electronotes, so I looked them up and discovered they were both inspired by and heavily influenced by Burhans, particularly in terms of the comb filter frequencies and spacing. One was a 40 channel version by Ian Fritz using transistor based filters. He had an interesting mod, originally suggested by Lester Ludwig, where each set of 6 filters had a feedback pot. Some screenshots from these articles are at the end of this build guide. The relevant Electronotes issues 107, 115 and 116 can be found online.
The Bernie Hutchins design used 39 regular op amp based filters, along with Ian’s feedback per 6 filters mod and added an inverter so the feedback could be positive or negative (so, centre off). Negative feedback ‘flattens’ the peaks somewhat and smears the sound, positive feedback makes the peaks narrower and higher (if tuned for it, you can make them self-oscillate, see notes). Bernie also added a noise gate on the output, summing 39 channels is always going to be noisy.
It is based on ideas presented in an AES article by Ralph W. Burhans
Using the switches, pots and signal input, you can create patterns as simple or as complex as you like.
It is not a 6 stage sequencer as most settings enable more than one channel to be active at once and the CV output is a sum of the voltages set by the pots connected to the active stages.
The switches enable extremely long patterns to be generated. The signal input allows you to change and randomise patterns on the fly, but it fun to flick the switches back’n’forth (centre is off); sometimes you might even return to a previous pattern. It is also fun to feedback a gate output into the signal input to create shorter loops that can be altered with the switches as well.
As a timbre generator, it can add harmonics to sine waves or step in and out of pseudo random noise as the signal and/or clock are CV controlled. It might be good to feed the output to a VCF to smooth some of the edges, but it depends on how noisy you want it.
"@WeAreElektron Tonverk & Eurorack
@afterlateraudio Adventure case & Atom
Neutron Sounds Dust of Time
@QuBitElectronix Scanned
Gehrin Plaits
@makenoisemusic QPAS
@EricaSynths Black Joystick 2
Nonlinearcircuits Triple Sloths V2
@NoiseEngineering Manis Iteritas & Viol Ruina
Livewire Electronics Vulcan Modulator
@1010music bluebox
Live visuals using Year 2889 (1969) from Archive.org played through cracked ancient iPad and processed through: Video microscope
Sony ZV1
Roland V1-HD
@entropyandsons Recursion Studio
Resolume Avenue
Recorded with Rodecaster Video"
Elektron Tonverk vs Eurorack Modular - Making feedback drone tones
00:00 Intro ramble - The Idea!
01:15 The Atom - Elements Clone
04:00 The Tonverk FX - Filter Folder
07:17 The other bits of the Tonverk
08:42 Joystick control and other modulations in the patch
14:32 Let's listen to the feedback patch
18:27 The feedback sample on the Tonverk - Do you Sub bro?
20:51 Let's listen with the kick & rumble
22:24 One more input into the Atom for extra feedback drone tones
26:18 Neutron Sound - Dust of Time layer
29:29 Plaits drone
30:39 All together now!
@WeAreElektron Tonverk & Eurorack @afterlateraudio Adventure case & Atom Neutron Sounds Dust of Time @QuBitElectronix Scanned Gehrin Plaits @makenoisemusic QPAS @EricaSynths Black Joystick 2 Nonlinearcircuits Triple Sloths V2 @NoiseEngineering Manis Iteritas & Viol Ruina Livewire Electronics Vulcan Modulator @1010music bluebox
Video: Live visuals using The Time Travellers (1964) from Archive.org played through cracked ancient iPad and processed through: Video microscope Sony ZV1 Roland V1-HD @entropyandsons Recursion Studio Resolume Avenue Recorded with Rodecaster Video
single 1U version - https://www.nonlinearcircuits.com/mod..."
"This module is a set of 4 reverse sigmoid chaos circuits, running at different frequencies, there are pots to feed each section into another and influence, sync – sort of, the action. There are also CV inputs for each section which affect the reset or crossover timing, for the faster ones the results are obvious. For the slower ones, give it a few hours.
The reverse sigmoid circuits are similar in concept to the mackey-glass based design used in the NLC Frisson, but are greatly simplified to a bare minimum of parts. Simply an integrator, two all pass filters and a nonlinear stage with two feedback paths. The nice thing about them is you can use any capacitors you like, so long as all three are the same, and the circuit will work with no other mods required. The sections in this module use 1uF, 10uF, 2x 1000uF in series (so 500uF) and 2x 2200uF in series (so 1100uF).
They work quite differently to the Sloth chaos circuits, with a number of ripples or rolls between each attractor, also the three outputs track each other, the faster ones are delayed by a few seconds, the slower ones by minutes. The intent of having 4 different circuits running together with pots to get them to influence each other is to have a module that can create longer tracks with many different but related musical events happening and, of course, weird delayed CV effects. Think of a band where the members all do their own thing but every now and then the sounds and patterns connect and achieve structure, which slowly scatters and reforms in new ways.
Feel free to change the 1uF caps to a higher or lower value, similarly for the 10uF. Stack capacitors on top of each other to get 20uF, or use Tayda 22uF caps and stack them. See pictures on pg6 for info on which caps to change. Make sure the capacitors have at least a 25V rating or higher.
If you want to use larger values than 1000uF and 2200uF, make sure they will fit on the PCB and/or thru the panel holes (1000uF on PCB are 10mm diameter, 2200uF panel holes are 16.8mm)
There are also two difference rectifier circuits which output complex mixes of the individual chaos circuits."
1U REVERSE SIGMOID DESCRIPTION/USAGE
6hp
This module is a reverse sigmoid chaos circuit; it can be built to run as a fast or slow CV source, or even as an audio/noise source. This is a single version of the four chaos circuits in the NLC How’s the Serenity module.
The reverse sigmoid circuits are similar in concept to the mackey-glass based design used in the NLC Frisson, but are greatly simplified to a bare minimum of parts. Simply an integrator, two all pass filters and a nonlinear stage with two feedback paths.
The nice thing about this design is you can use any capacitors you like, so long as all three are the same the circuit will work with no other mods required. The capacitors are marked ‘C’ on the PCB, 1uF is a good mid-range value to install, but 10uF, 22uF are good too albeit much slower. Lower values than 100nF get you into audio rate territory. Make sure the capacitors have at least a 25V rating or higher.
This works quite differently to the Sloth chaos circuits, with a number of ripples or rolls between each attractor, also the three outputs track each other, the faster versions are delayed by a few seconds, the slower ones by minutes.
The Input expects a positive CV, negative going CVs won’t hurt but will have no effect. The CV signal feeds into the first all-pass filter stage via 10k and a diode, this is different to the method used on How’s the Serenity. On slower builds, using 10uF caps, the effect of the CV will be washed out to some extent. It will still have an effect but not as noticeably as on the faster versions.
"A super quick demo showing the latest revision of the Cellular Automata prototype up and running. CV is just feeding an FM input of a sine wave oscillator to show the modulation. One more board revision and it’s ready for public consumption.
Gate outputs (not used in this video) will be buffered and designed to be stack in OR logic configuration. Which makes for quick gate patterns to be made."
"This module is a 4HP version of the NLC 8HP Neuron & Difference Rectifier.
The differences are half the panel real estate, SMD components, LEDs to indicate activity and one less input on the Neuron (2 instead of 3).
From the original version description -
The Neuron was inspired by a paper on neural computing and is a variation of a typical analogue neuron circuit. It can be used as a complex audio waveshaper, gate or pulse generator, CV shaper or to generally mess things up. The diff-rect is a hybrid of two basic op amp ‘building blocks’ – a difference circuit and a rectifier. Not sure if I have ever seen the two merged together before. It is probably a bad idea except for synth use, where it is a wonderful idea!
The Difference Rectifier has 4 inputs (two + & two -) and two outputs. The Neuron has 3 2 inputs and one output, the pots control when the neuron will react to incoming signals and how much it will react."
Bean Jelly stereo: both low pass and band pass outputs goes into
NLC diff-rect, and then into stereo inputs of Oneiroi.
Oneiroi looper plays a Bean Jelly recording.
Bean Jelly rungler modulates Oneiroi looper start and resonator.
Other modulations on Oneiroi are internal chaos lfo and random morphing.
Recorded live thru Syntakt inputs with delay and reverb
"This is how my nightmare sound like, quick patch on my modular system and Plinky
Bowed noise is Elements Poly is plinky "Windy" noise is paralel procesing of the bass line to ruina versio filter by ikary using the 2 even and odd output of the resonantFB Bass is NLC fm op, to waveshaper to vacium tube with feedback to resonant FB filtered by centaur gate Arp is NLC FM op, phase modulated, mixed with noise filtered by centaur gate Arp is paralel pocesing to Typhoon using spectral madness algo, with manual modulation using Allflesh.
All this mixed with jumble henge to polydactul versio to Bib for effect
Thank you for watching. My name is Meska of the statik collective . I've been making mostly "dark and expérimental" music for more than ten years now, i'v learn so much online, now it's time for me to share my knoledge, my exploration and this channel is a place to talk about the tools, sound design and techniques to make music with.
"This is how my nightmare sound like, quick patch on my modular system and Plinky
voice: to warp vocodeur(parasit)
poly : plinky
noise: reso eq even& odd outût to riuna versio, and ikary
bass line NLC fmop phase modulated , to LPG to res eq, in doppio.
lonely cry: NLC fm op self phase modalted, to waveshaper in to wmd carbon feedback the BP out to fm in.
This voice into typhoon for texture
a little bit a buzzy at the end
All mixed with jumble henge, into polydactyl versio and Bib for the FX
Thank you for watching.
My name is Meska of the statik collective . I've been making mostly 'dark and expérimental' music for more than ten years now, i'v learn so much online, now it's time for me to share my knoledge, my exploration and this channel is a place to talk about the tools, sound design and techniques to make music with.
"I built a Nonlinear Circuits Bindubba Sequencer eurorack module. The background music was made using my eurorack setup featuring the Bindubba Sequencer. The build took about 7 hours.
00:00 Intro to the kit
00:50 ICs
04:53 Transistors
07:28 Resistors, Capacitors, and Diodes
16:02 Rectifiers, finishing up resistors and capacitors
17:00 Power Pin Header
17:21 Vactrols
18:15 Minijacks, Potentiometers, and LEDs
23:05 Test 1
23:58 Troubleshooting
24:55 Test 2
25:30 Finishing up/Outro"
"Macrame is a 6 channel mixer with voltage controlled level and panning. It uses two SSI2190 chips to do all the work.
You can use the SET pots to operate the level and pan manually, or use CV to get things moving around and up and down.
It has two synth level outputs, two line level ¼” jack outputs and a stereo line output (which works fine with most headphones too).
For some reason, probably because I was slightly askew on post-op painkillers when designing this, the panel is 21HP. I guess this means I need to release more odd HP modules to avoid gaps in cases."
"Logorrhea is kind of a vocal filter; basically it is the back half of a vocoder crammed into 8HP. There are two inputs, 10 filter channels, a white noise channel and a thru channel, to feed thru the original signal(s). It uses two SSI2190 chips to do all the work.
There are no knobs.
To use, patch in one or two audio signals. Ones with lots of harmonics sound best, pulses, squares or wave-folder outputs, not sinewaves.
Patch in a bunch of CVs to set up your sounds, it expects 0-5V CV signals.
OUT is all channels mixed together.
OUT A is thru, LP (low pass), BP2, BP4, BP6 and BP8 (BP = bandpass).
OUT B is noise, BP1, BP3, BP5, BP7 and HP (high pass).
Using OUT A and OUT B in a stereo mixer (such as NLC Macramé) is nice with panning to move the sounds around."
"This module uses the SSI2140 chip which is based on the SSM2040 VCF, tho with a few updates.
My first thought when I read the datasheets was that it would be great to design a module that could switch between a phaser and a VCF. Looking back at old SSM2040 designs, it seems most of the usual suspects (T. Henry, J. Blacet, C. Anderton et al) had much the same idea.
This module is based on Anderton’s design in Device 1-6 (yes, I spotted the error) with modifications to suit the SSI2140 and Eurorack.
There are 4 switches, one for each OTA stage, to select between (all pass (phaser) and low pass filter mode. You can have quite a lot of fun with 2-3 switches in one mode and 1-2 in the other.
There is a dry mix pot to mix the incoming signals into the OUT signal, which is taken from the 4th OTA stage. This is probably more commonly used in Phaser mode, but there are no rules, so do whatever you like.
POLES is a weighted mix of the outputs of each pole, it is a bit shy when all switches are turned to Low Pass but perks up very nicely when one or more switches turned to Phaser.
The SSI chip is a bit tight to solder, have your bottle of flux ready, otherwise it is a pretty easy build."
