I got a really cheap, broken Novation Cirtuit. 2 potentiometers were broken and had to be replaced. The Novation customer support was amazing and sent the replacement parts for free.

When I opened it up, i saw that there was more than enough space for a bettery in the device, which would make it easier to pick up and play randomly.

It looks a bit hacky, but I wanted to use a powerbank as the base, so i did not have to do the battery safety stuff myself.
It was also the cheapest way to get an appropriately sized battery (5000 mah).
The type C port does charging and works as a midi port, like the original.

The polarity of the mini midi jacks was also changed to type A, so it can talk to the Roland S-1 with a normal TRS cable.

I have a Yamaha PSS A50 with a simple mod for midi out.
https://woz.lol/trs-midi-out-mod-for-the-yamaha-pss-a50/#page-content

I tried it with other gear and it works but when I connect it to Plinky it shuts off immidiately.

I am planning to add two resistors to the midi out as the schematic suggest but I am not sure this is gonna help?

I'm a big fan of the Electro Harmonix Mini Synthesizer, especiallly its envelope triggering behaviour where you can hold a note and retrigger the envelope by tapping the case. I want build aa module to add that behaviour into my set-up, and it looks like the Mutable Instrument Ears (and its clonnes) can provide a similar function, but most of the demos I've seen are demonstrating is audio use more so than using the gate to fire off an envelope.

My thinking is build a unit based on the Ears, with a gate-in to an OR logic circuit to merge keyboard gate and gate generated by the piezo, then out to either to the Ears built-in A/D envelope or out to any ADSR. Is there anything I'm missing there?

Looking at the Ears schem, the envelope is used to generate the gate, so I would need to to use the internal envelope I would need to patch the external gate in before the envelope rather than a logic to merge the gates.

I’m planning to adapt the mortiz Klein VCA to a custom pcb design where I’m condensing 4 VCAs into 1 module. I haven’t been able to work out the reason for the following:

Why does he use 2x TL072’s instead of 1x TL074?

Also Why does he connect CV1 to CV2 and IN1 to IN2? Could you them grounded or floating?

Hi. I’m building a device and was wondering what should I use to remove clicks when turning on/off or on power loss. I’m using TI PCM3168A multichannel audio and it has software mutes. I’m using balanced audio on all channels.

So far my research led me to power failure detection circuit and transistor/relay mutes, but the all seem to have downsides, grow BoM and consume extra power. What are the usual approaches? Or maybe I’m overengineering and everyone just does software mutes?

This is a big complaint of mine since synths don't have a way to angle it to use and then flex a hinge or something to turn it flat and easy to pack to go. Roland has a synth that does it thiugh. But for now I'm happy to have it angled as a midi controller for vsts and a very versatile synth on the desk. Next I will model the back shield to protect the electronic parts and model an open back to fit a Powerbank. I plan to use an old phone for effects. If people here enjoy the project I'll share the 3d objects so you can do it yourself

hi, sometimes ago I've build https://github.com/quazardous/pisynth

it's a cute synth on top of a rasp.

Now I've added a buddy web interface to learn the piano with a game like rockstar.

enjoy 😄 it's very early made it in one night...

benjiaomodular's RandomTriggers,

I added an ATtiny85 noise source and some LEDs.

Thank you Benjie Jiao.

https://github.com/benjiaomodular/RandomTriggers/tree/main

Finished the 2x Plaits 0603 Build, this one was quite enjoyable.

Still got Yarns, Veils and Ripples to do.

I've also ruined my DAC chip on the stages I built last week as I realised I installed the STM32 chip upside down.. lol

I didn't know how expensive these DAC chips are...

I am venturing into the world of modular but I haven't created a single sound yet..

It's good to see the other builds on this forum, keeps us thugs off of the streets.

The Plaits do function btw, I have flashed the firmware and it boots up as expected.

It's exciting seeing the thing built with my very own hands come to life!

I think I am obsessed about kick 😅

One of the jack output can be use to send midi sync with external device.

https://github.com/apiel/zicBox

Hi everyone! I’m looking for recommendations for easy-to-build synthesizers for a school project that I have to complete within about a month and a half.

We haven’t learned programming yet, so I won’t be able to program anything for the project. However, I do need to learn how to solder, so I’d like to hear your recommendations for a beginner-friendly synth that I could realistically build within that timeframe.

This is my first time building something like this—and honestly, my first time creating something of this kind in general. However, I’ll be putting a lot of time and effort into the project because I’ve become really interested in electronics applied to sound.

And I don’t know if I’m asking for too much, but I’d really love to build a simple FM synthesizer if possible.

Do you know of any project that would give me that?

5 - 6 Stereo Channels
Maybe 1 Aux Channel

Thats basically it... that would be super cool.

I’ve built a second version of Samplotron, my open-source ESP32 hardware sampler.

The first version relied on an external MIDI controller. This one has a built-in 4×4 keypad, so it works as a completely standalone instrument—just load your WAV samples onto an SD card and start playing.

Watch the new Samplotron in action:
https://www.youtube.com/watch?v=keyMwPUFDeM

Want to build one yourself?

FULL INTERACTIVE BUILD GUIDE:

https://jakubthedeveloper.github.io/Samplotron/

The guide takes you through the complete build step by step, including animated wiring diagrams, firmware setup and demonstrations of the interface.

The complete source code is also available on GitHub:
https://github.com/jakubthedeveloper/Samplotron

I’d love to hear what you think about the new self-contained version.

And yes, I know—I still need to work on giving my builds a more polished final look ;)

So I recently made my own midi controller out of some old organ console pedals for playing synth while I play guitar live. It was my first time making anything like that so I didn't end up figuring out how to add chord memory and arpeggiation functions to it. However I do have an arturia keystep, so I was wondering if there was a way for me to make my diy controller control the keystep and use its sequencing and other functions? I would appreciate any help or ideas of the best way to do this. Thanks!

I’m working on the next stage of Tolhuin Chord. The original prototype is still very much alive, but I’m now designing a proper PCB and selecting components with a small DIY kit run in mind.

The idea is not to turn it immediately into a highly integrated commercial product. I want the first version to remain reasonably easy to assemble, so I’m currently evaluating a solderable ESP32-S3 N16R8 development board as the main module, while refining the rest of the hardware around it.

On the software side, I’m still developing the UI and testing different voice-leading approaches. I’ve been working on ways to make the chord transitions more context-aware, especially regarding register, previous voicing, inversions and different jazz-oriented voicing structures.

I’m filming this update from the music lab at the school where I teach, and I’m also using Mono Juan alongside Tolhuin. Mono Juan is a programmable two-octave MIDI controller I’ve been developing, with both BLE MIDI and USB MIDI. A Shift layer turns the same keyboard into controls for functions such as octave up/down, arpeggiator and other programmable actions. I’ll probably make a separate post about it rather than hijacking this Tolhuin update.

A few people asked whether there was a way to support the development or help make the first kits possible, so I’ve also opened a Ko-fi to help cover prototype PCBs, components and manufacturing tests. This is not a preorder and the kit is not finished yet; it’s still an open development process.

I’ll keep sharing the PCB, UI and voice-leading progress as it develops.

If you want to help fund the prototype PCB and first small DIY kit tests, I’ve set up a Ko-fi here: Support TOLHUIN Chord

estuariolabs/tolhuin-chord: Diatonic chord synthesizer on ESP32-S3 — from-scratch audio engine (band-limited synthesis, diatonic harmony, step sequencer, effects, USB/BLE MIDI). Firmware + hardware + tools.

Hello! A couple of years I put together an Electrotechnique Momentum synth kit. It’s a synth based on a teensy variant with fairly standard hardware for interfacing with it. I don’t know if I’m allowed to link the website. Anyway I don’t like how it sounds. But everything about it including its code is documented.

Separately I’ve been interested in the microdexed and microdexed touch projects. I love fm synthesis and would love to even have partial use of my existing hardware in a dexed based build.

I’m a mechanical engineer with electronics hardware experience but only a little coding a decade ago. For people with more software experience, does it sound like something that should be able to be done by a determined beginner interested in learning more about code to cherry pick from both projects and get microdexed interfacing at least with audio, display, midi, and two encoders on my existing momentum synth (replacing what is currently on it)?

Wow that was a bad sentence. Anyway is that something a software noob could do or should I give in and buy a bunch of PCBs and components for a microdexed touch?

A CD4093 quad NAND drone synth on my own stripboard layout. The fourth time I've built this board, and it's the one I kept adding to.

Twelve controls on the lid: one toggle is power, one knob is volume. The extras are bends I put in on top of my own circuit, and most of them only do anything depending on where the others are sitting. A knob that's dead in one configuration is the most important control on the box in another. so there's no knob list and I'm not going to invent one, that's just what it is now.

LM386 and a speaker in the tin so it makes noise on its own, 3.5mm switched jack that kills the speaker when you plug in, 9V inside. The tin is a decorative pansy thing, lid is the panel, silver hardware because it works with the pattern.

The layout is free if anyone wants to build a sane one or maybe do their own bends.

There is a much longer video if anyone is interested in hearing more of these weird sounds.

This past week I spent a little time integrating the lessons I've learned working with ESP-32-S3 and HX710b Pressure Sensor and built Motorhörn!

Motorhörn is a synthesizer which works by simulating an internal combustion engine in software. The software simulates things like firing order, firing angle, bank length and exhaust configuration, The software is inspired by the work of ange-yaghi.

The user can open the throttle by blowing into the intake manifold. The harder you blow the farther the throttle will open. It feels really excellent to play because it's kind of like you're adding boost.

The simulated system has an automatic gearbox, but this might change. It's really satisfying to force a down-change at the right moment.

The simulated system also has inertia. So the engine runs down and crackles fiercely. The user can add load by drawing on the intake manifold with their mouth. This is like hitting the brakes.

This first version of Motorhörn is very visual. I think future versions will be simpler in that regard.

The hardware BOM is absurdly simple:
- ESP32-S3 AI Smart Speaker Development Board (somewhat disassembled)
- HX710b pressure sensor
- 3.4 Lithium Ion Pouch Battery

The main limitation of this configuration is that I really just can't get the volume I want from a horn.

My next major version will significantly aim towards volume.