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ST Modular is a company specializing in the design and production of modular synthesizers. They offer a wide range of Eurorack modules. Their designs often focus on affordability and DIY kits, allowing musicians and enthusiasts to build their own sound modules while experimenting with modular synthesis. ST Modular is known for producing innovative, compact, and functional designs that cater to both beginners and experienced synth users. Home

DII·ONE is a compact MIDI controller and routing hub designed for modern hybrid music setups.   It combines USB MIDI, hardware MIDI, and a CV clock output in a single device, allowing all functions to operate simultaneously without compromises. rattlecore / piezo pre-amp PCB with high-pass filter / PCB only ⇣ Rattlecore is a compact, high-gain piezo preamp PCB with integrated high-pass filter designed for DIY noise boxes, contact mics and experimental sound sources. key features High-quality OPA1656-based preamp Adjustable gain from +10 dB up to +50 dB Integrated high-pass filter (47 Hz – 4.8 kHz) Optimized for piezo contact microphones Clean virtual ground via TLE2426 rail splitter Onboard power LED Protection diodes on input Compact PCB for easy enclosure builds Designed for 9V DC operation (battery or DC) Soft grounding option for enclosure → documents RATTLECORE_QUICK_START_GUIDE.pdf description / manual Rattlecore is a dedicated piezo microphone preamp and filter circuit designed for experimental sound design, noise instruments and DIY contact mic boxes. The circuit is built around a low-noise, high-performance op-amp stage and provides enough gain to bring even very weak piezo signals into a usable audio range. The gain can be adjusted via an onboard potentiometer, allowing anything from subtle amplification to aggressive boosting for noisy textures. A second stage implements an adjustable high-pass filter . This helps to remove low-frequency rumble. It also allows you to shape the tonal character of your sound source, from deep thumps to sharp clicks and textures. The PCB uses a virtual ground (rail splitter) to run cleanly from a single 9V supply . This keeps the design simple and makes it ideal for standalone DIY builds. This is not a complete instrument. The PCB design is provided as a DIY project component. You will need to: add your own piezo sensors build or design an enclosure add jacks, controls and mechanical parts install power supply socket or battery The design is intended for DIY builders who want to create their own custom noise boxes or experimental instruments. RattleCore works especially well with piezo contact microphones that capture vibrations from: metal objects springs surfaces resonant bodies Every build can sound completely different depending on what you attach to it. DIY Build Example Wooden enclsoure made by barebaric.com Up

DII·ONE is a compact MIDI controller and routing hub designed for modern hybrid music setups.   It combines USB MIDI, hardware MIDI, and a CV clock output in a single device, allowing all functions to operate simultaneously without compromises. digital instrument interface one / usb midi interface and controller / 0 HP ⇣ DII·ONE is a compact MIDI controller and routing hub designed for modern hybrid music setups. It combines USB MIDI, hardware MIDI, and a CV clock output in a single device, allowing all functions to operate simultaneously without compromises. key features Compact USB MIDI controller with hardware MIDI I/O and CV clock output 4 programmable buttons (CC or Note, momentary or latching) 4 programmable knobs (assignable to any MIDI CC) USB MIDI to and from computer TRS MIDI In and Out (5-pin DIN compatible via adapter cable Type-A) CV Clock output for modular synthesizers (0–5 V) Hardware-based MIDI Learn Clock division directly from the device All functions usable at the same time → documents DII_ONE_QUICK_START_GUIDE.pdf ST_Modular_DII_ONE_Configurator_v7_2_0.zip description / manual The control surface of the DII·ONE MIDI controller is intentionally minimal and focused: Four freely programmable pushbuttons and four knobs provide direct access to the most important parameters without unnecessary complexity. Each button can be configured to send MIDI CC or Note messages and can operate in either momentary or latching mode, making them suitable for triggers, toggles, transport functions, or performance controls. The four knobs offer smooth and precise control over continuous parameters. Each knob can be assigned to any MIDI CC and adjusted in range, sensitivity, and response. This allows slow, detailed parameter changes as well as fast and expressive movements during live performance. Connection options are designed for maximum flexibility. Via USB, the DII·ONE provides bidirectional MIDI communication with a computer and is class-compliant, requiring no driver installation. It integrates seamlessly with all common DAWs and can be mapped instantly using MIDI Learn. In addition to USB MIDI, the DII·ONE features TRS MIDI In and Out for direct connection to hardware synthesizers. Using appropriate adapters, it is fully compatible with standard 5-pin DIN MIDI connections. This allows the controller to act as a bridge between computer-based setups and external hardware or even between to hardware synths. A dedicated CV Clock output converts incoming MIDI clock signals (from USB or TRS MID IN) into stable 0–5 V analog pulses, enabling modular synthesizers to stay perfectly synchronized with a DAW or hardware sequencer. Clock divisions can be selected directly on the device, offering a wide range of rhythmic relationships from straight timing to more complex divisions. MIDI routing can be adapted to different workflows using selectable MIDI Thru modes . The DII·ONE can operate as a pure controller, a MIDI interface, or a bidirectional routing hub. USB-to-TRS routing allows the computer to control external gear, while TRS-to-USB routing enables recording MIDI from hardware into a DAW. For advanced setups, bidirectional routing is available, allowing all connected systems to interact simultaneously. The integrated MIDI Learn function makes assigning controls fast and intuitive. After activating Learn mode, moving a control on the DII·ONE and sending a MIDI message from a DAW or synthesizer completes the assignment, which is then stored permanently in the device. Once configured, the DII·ONE operates fully standalone without requiring a computer. For deeper customization, the optional web-based configurator gives you complete control, from button behavior and knob response to MIDI routing, clock settings, filtering, and live MIDI monitoring. In addition to the basic functions, you can also set up enhanced MIDI controls, such as fade-ins and fade-outs on pushbuttons, or use a single knob to control two CC values simultaneously, for example for crossfades. You can download the configurator HTML-file (*.zip) by clicking on the picture below. Typical Applications The DII·ONE is ideal for hands-on control of DAW parameters, MIDI control of hardware synthesizers, recording MIDI performances into a computer, and MIDI-sync hardware-synths and CV-sync modular systems via CV clock. Its ability to run all functions simultaneously and its compact format makes it especially suitable for hybrid studio and live performance environments. Technical Specification Push Buttons: 4 Knobs: 4 USB: USB MIDI (bus-powered) MIDI: TRS MIDI In / Out (Type A) CV Output: Clock, 0–5 V Clock Divisions: 1:1, /2, /3, /4, /5, /6, /8, /12, /16 MIDI Learn: Yes Web Configurator: Yes Standalone Operation: Yes (internal memory) Up

ST Modular is recognized for its DIY Euroack Modules that enable users to construct their modular synthesizers utilizing provided PCBs and self-obtained components. The range of modules offered encompasses oscillators, filters, sequencers, LFOs, envelope generators, and more, all designed by ST Modular to be exceptionally versatile. These modules facilitate a broad spectrum of sound manipulations and modulation avenues. NEW! DII·ONE USB MIDI INTERFACE AND CONTROLLER NEW! RATTLECORE PCB PIEZO PRE-AMP WITH HIGH-PASS FILTER / PCB ONLY NEW! PASSAT PASSIVE ATTENUATOR / 0HP NEW! HONEYEATER V3 CEM3340 ANALOG VCO WITH SUB-OSCILLATOR / 6HP appetizer social media youtube modular grid instagram tiktok krakong euphoria Up

Oscillator eurokastle / eurorack version of the bastl kastle / 10 HP ⇣ This is a Eurorack adaptation of the renowned Bastl Instruments Kastle – a digital synthesis playground. Embodying the full spectrum of Kastle 1.5 functionality, this version features subtle modifications to seamlessly integrate into the Eurorack format. KASTLE_BACK.jpg 1/3 key features Please check out the Bastl Desktop Synths for further details and consider buying one - it´s worth it! Use with Bastl Kastle or Drum Kastle Firmware Illuminated EuroKastle Logo Wrong Polarity Protection specs & downloads width: 10 HP depth: 28 mm power: 47 mA @ +12V documentation videos description / manual Switching between OSC mode and Rungler mode has been streamlined with a convenient switch, eliminating the need for intricate cable patching. Furthermore, each functionality is consolidated to a single input/output, simplifying your setup. Notably, our EuroKastle boasts a unique Waveshape CV attenuator absent in the original Kastle design. While we highly recommend Bastl's desktop version, the EuroKastle can stand independently. You can independently source all the required components, without necessarily needing the original. It's important to note that the PCB lacks an AVR ISP header. To program the Attiny85 ICs, a prior flashing process is essential before they find their place in the IC sockets (a breadboard can be utilized for this purpose). The programming process can be completed using any AVR ISP programmer. Powering the EuroKastle is a breeze with compatibility with standard Eurorack power supply units. Version V2 introduces AVR Headers to the PCB's bottom for direct ATTiny programming on the PCB itself. The diode pads have been thoughtfully enlarged for an enhanced soldering experience. Additionally, the CV Sources are normalized to the CV Input switches, facilitating instant modulation without the need for external patching. In Version V3, we've incorporated a jumper that allows you to transform the Mix OR OUT socket into a TRIGGER INPUT for the Drum Kastle firmware, enhancing your creative possibilities. For those seeking additional technical details and resources, we encourage you to explore the following links: Bastl Schematics Bastl Instruments Official Website prev Up next

Effects buff / analog distortion and sustainer / 4 HP ⇣ BUFF is a straightforward yet potent distortion module that can significantly enhance your sounds. It introduces a rich fuzz texture to the input signal, all the while preserving a clear bass and delightful high-frequency response. 1/3 key features Analog Distortion/Sustainer Easy to Build and Cost Effective Tone Control Sustain Control Level Control Wrong polarity protection specs & downloads width: 4 HP depth: 28 mm power: 25 mA @ +12V / 61 mA @ -12V documentation videos description / manual BUFF can turn any weak-sounding tone into an earth-shaking experience and is especially suitable for creating haedbanging techno percussions. Equipped with a TONE control for accentuating low or high frequencies, and a SUSTAIN control that facilitates the creation of a protracted and velvety sustain. LEVEL dictates the degree of distortion infused into the signal. Kindly be aware that rapidly adjusting the TONE knob may introduce a DC offset, leading to a momentary fading of the sound. Unfortunately, addressing this issue would compromise the delightful quality of the sound in its current state. Kindly decide in advance, whether you are soldering or purchasing the module, if this is a matter of concern for you. prev Up next

Oscillator give v2 / classic analog vco with sub-octaves and waveform mixer / 14 HP ⇣ GIVE V2 is a sonic powerhouse that transcends the boundaries of traditional sound generation. The module is an exceptional analog VCO accompanied by a versatile waveform mixer and three suboctaves 1/3 key features Classic Analog VCO 5 Outputs: SAW, TRI, SUB, NOISE, PULSE 1V/Octave tracking Pulse Width Modulation with Attenuator Frequency Modulation with Attenuator Integrated Waveform Mixer Skiff friendly design Wrong Polarity Protection specs & downloads width: 12 HP depth: 28 mm power: 31 mA @ +12V / 28 mA @ -12V documentation videos description / manual The VCO provides five outputs, the last four of them can be mixed with an integrated mixer:PULSE, SAW, TRIANGLE, 3x PULSE SUB & NOISE Patching a voltage/audio source into FM you can frequency modulate the oscillator. Incoming voltages can be attenuated with FM CV. In the middle of the module you will find the PWM potentiometer. Here you may change the pulse width of the pulse wave. The width may also be controlled via external voltage with the PWM jack and the PWM CV attenuator. Just like all other classic analog VCOs GIVE II also tracks one volt per octave with the help of the 1V/OCT input jack. Each wave can also be hard-synced by an external wave patched to the SYNC jack. In addition to the classic VCO functions GIVE II also provides an integrated frequency divider. The MIX output jack will not only supply the waveforms SAW, TRIANGLE and NOISE, but also provides up to 3 sub octaves derivated from the PULSE waveform. The volume of each sub-octave may be adjusted with the potentiometer SUB 1-3. ORIG will adjust the volume of the original PULSE signal. Using the switch ORIG SQU you can flip the SQUARE waveform. prev Up next

Sequencer push / manual sequential switch / 4 HP ⇣ This module was inspired by Make Noise „Pressure Points“, which has three rows of four tunable voltages. PUSH takes one of these rows in order to play melodies, change timbral settings of oscillators or even to store simple presets for a given parameter of any other module in an HP friendly design. 1/3 key features Manual Sequential Switch Four Voltages Loop Sequence in 2, 3 or 4 Steps Reset to Jump to Step 1 Variable Maximum Voltage via Trimmer Pot LED Indicators Wrong Polarity Protection specs & downloads width: 4 HP depth: 28 mm power: 35 mA @ +12V / 30 mA @ -12V documentation videos description / manual PUSH is a single four position manual sequential switch. There are four steps, each with a potentiometer to set a specific voltage. With a push on the PUSH button one of these values is selected and supplied at the OUTPUT jack. The sequence always starts with the first step and you may switch through the other three potentiometer/voltages sequentially. The sequence will loop when you have reached the last step and press the button further more. You can set the length of the sequence from 2 up to 4 steps. With the help of the RESET button you may jump to the first value at any given time. Additionally you can simultaneously change the maximum voltage of all four steps from 5V to 10V with the help of the little trimmer pot VR on the top. You can choose to have any voltage between 5V and 10V. Turning the trimmer pot will instantly change the value for all four potentiometers. prev Up next

Oscillator yaksha´s fate / mutable instruments "rings" adaption / 8 HP ⇣ In this rendition, the emphasis was placed on showcasing all the adjustable parameters prominently while concealing those that could impact tuning and harmonics. This design approach allows you to immerse yourself in uninhibited live performance, without the concern of inadvertently altering frequency or structure, ensuring a seamless experience for both you and your audience. 1/3 key features Please check out the original module by Émilie Gillet which is an all time Eurorack classic already Illuminated Yaksha´s Fate Logo Wrong Polarity Protection specs & downloads width: 8 HP depth: 38 mm power: 125 mA @ +12V / 12 mA @ -12V documentation videos description / manual It has all the functionality of the original module except for the two Outputs Odd/Even, Frequency CV (also Fine Tune) and Structure CV (Harmony). You may switch Filter CV or Decay CV to control Harmony via jumper though. The two outputs Odd and Even are mixed together on the OUT jack, but you can fade from one to the other using the Partial Knob. This way you get an additional sound shaping option and some kind of trigger control when two or four notes polyphony is selected. In contrast to the original Yaksha´s Fate will rather act as a VCO producing a constant tone (through very fast trigs) if you plug a CV source into 1V/OCT without a trigger at the TRIG input. Released under cc-by-sa-3.0 license: Pichenettes Mutable Instruments prev Up next

1U Module slide / 2 channel mixer/fader / 12 HP ⇣ SLIDE is a very simple but powerful 2 channel mixer with just one slide potentiometer. 1/4 key features 2 Channel Mixer 2 Inputs, 1 Output Slide Potentiometer Potentiometer LED indicating Voltage State Available in Intellijel and Pulp Logic Tile Format Convertable Flip Panel Skiff friendly specs & downloads width: 12 HP depth: 25 mm power: 20 mA @ +12V / 15 mA @ -12V documentation videos description / manual With two input jacks and one output jack in the middle you can mix or fade any audio or cv singnal with the slide potentiometer. This module is available in the Intellijel 1U format as well as in the Pulp Logic 1U Tile format. Additionally the panel is convertable in order to flip it upside down, if you want to have the jacks at the bottom of the module. prev Up next

Utilities & PSU once in a while / 3-channel mono, 1-channel stereo CV click-less mute / 6 HP ⇣ Tired of muting with all the drama of a Shakespearean tragedy? Say goodbye to the click drama with our click-less mute module. It's like giving your modules a chill pill – no more dramatic exits, just smooth audio bliss. 1/4 key features 3-Channel Mono Mute 1-Channel Stereo Mute Click-Less Muting based on Vactrols STRIKE Buttons for Performance Mutes LED Indication MUTE or GATE Mode for Channels 1-3 Wrong polarity protection specs & downloads width: 6 HP depth: 35 mm power: 25 mA @ +12V / 14 mA @ -12V documentation videos description / manual ONCE IN A WHILE is a 3-channel mono and 1-channel stereo mute switch with CV control. Any audio or CV signal fed into the IN jacks and taken from the OUT jacks can be muted and unmuted with a latching MUTE button per channel. If a channel is not muted, you can also mute it momentarily with the dedicated STRIKE button. Conversely, you can unmute a mono channel with the same STRIKE button if it is muted (this is not possible with the stereo channel). LEDs indicate whether a signal is being passed. You can also use CV signals to mute channels. Just connect a gate, LFO or envelope to the CV inputs and the channel will be muted from a voltage of about 2 volts. Even if you apply a control voltage to the CV inputs, you can mute the signal with the MUTE (latching) or STRIKE (momentary) buttons. Before soldering the module, you can decide if you want to use one of the mono channels alternatively as a low-pass gate. It's a single resistor you need to change and a mono channel becomes an LPG when a CV signal is patched into its CV input. So if the channel is muted, it will be unmuted again when the CV input is high. Mute mode = CV mutes the signal when it is not muted. LPG mode = CV unmutes the signal when it is muted. The first input is normalized to the other inputs. Therefore, you can also use ONCE IN A WHILE as a 1 to 4 buffered multiple with individual mute switches. ONCE IN A WHILE was designed to provide click-free muting for audio signals, but has become much more performance-oriented with the addition of momentary STRIKE buttons and CV inputs. It was optimized to be used with the VTL5C9 Vactrol. You can also use other vactrols, but then you may get clicks when muting audio. prev Up next

Modulation & Random 2xlfo / dual analog lfo / 3 HP ⇣ 2xLFO is a simple dual analog low frequency oscillator with two waveforms each. 1/3 key features Dual LFO with 2 Waveforms each Triangle & Pulse Waveform via Switch Rate Range switchable Slow Range: 1 Cycle every 7 Minutes Fast Range: Low Audio Rates LFO Rate potentiometers Wrong polarity protection Skiff friendly specs & downloads width: 3 HP depth: 30 mm power: 15 mA @ +12V / 15 mA @ -12V documentation videos description / manual The module offers the choice between a triangle and square waveform, conveniently switchable. The rate can be finely tuned using dedicated potentiometers. A switch allows seamless adjustment from extremely slow to audio-frequency rates. The module features two LEDs that provide visual feedback on the current LFO voltage state. Beyond its traditional LFO functionality, this module also operates as a dual sound source. It's particularly well-suited for crafting tonal percussion sounds that don't require pitch modifications via CV. With a straightforward design, the module comprises only 19 distinct solderable components, making it an uncomplicated build. prev Up next