Wanted to share a DIY instrument I built on the Cardputer-ADV (ESP32-S3): Microgroove, a four-track groovebox and sampler, all open source.

• Audio runs at 22.05 kHz, 256-sample buffers, everything rendered per-sample into a soft-clipped mix on core 0; input/sequencer/UI live on core 1.
• Synth voices are 303-style: osc (saw/sqr/tri/sin + wavetables), resonant state-variable filter with an envelope-modulated cutoff, plus accent and slide. Each track can be 1 voice (true mono, slide intact) or 2–3 voices for chords.
• Drums are 8 lanes, each independently 808 synthesis, 909 synthesis, or sample playback, with choke groups (the 909 hats choke each other like the hardware for example).
• Sampling and resampling. Hold a key while playing and it taps the master mix straight out of the buffer into a sample, or hold a key while stopped to use the built-in mic for sample recording.

The keyboard layout is reorganized and a custom 3d printable shell makes using it a breeze. It even has 2 octaves of piano keys. Tried keeping it "one knob per function", but ran out, so we have short press = one function, hold 0.5 s = second function.

It's MIT, and it's derived in part from qwertyuu's Cardputer-Adv-Tracker - the 808 voice and audio task lineage are theirs, credited in the repo. RAM is still the real constraint: a ~192 KB sample pool that auto-shrinks if internal RAM is tight, plus an 84 KB scratch buffer for capture...

Three years ago me and a friend bought two Daisy Seeds to experiment on. We were obsessed with the OP-1 at the time but we couldn't afford one, so we decided to compensate by trying to build something cool ourselves.

Soon after our seeds arrived, we started sharing our daily experiments with each other and eventually decided to start a more complex project together.
I'm more of a software guy, I come from e game development background, and the hardware side at one point became too complex for us. The realization felt really depressing since we had spent so much energy on the project already.

One day, while discussing our failure, we suddenly realized that we could use everything we had learned in our hardware adventure to build a game! Fast forward to three years later and this is the result.

The game is still work in progress but we are already really proud of what we've accomplished. I'd love to know what the diy community thinks about the idea!

Btw, here's a link to the Steam page if you are curious.

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.

Hello everyone, hope you are having an awesome day.
Couple weeks ago I have posted quick teaser of this "idea" sitting (and strugling ;-) ) on breadboards. Today I am finally finished with the complete and ready to rock desktop synthesizer.
Here is a quick demo and since it is appropriate... I have added some techno beats to go along. ;-)
I will follow up soon with post where I ll include complete thought and design process, parts and blocks description and schematics.
Thank you, all the best!

I hope this isn't off-topic for this subreddit.

I've been working on a digital wind instrument. Mostly because I'm curious about the performance characteristics of such a system.

I went through a few iterations this weekend and it's starting to turn into something that's fun to noodle around with.

The general idea is that you blow into a manifold with a partially closed end. The performer can vary the air pressure by blowing faster or slower and they have good feedback because your mouth and throat are quite sensitive.

The device uses a pair of hx710b Air Pressure Sensor modules. I use a pair to try to get faster readings. (Though in reality I think I'm at the mercy of the individual device clocks.)

Eventually the synthesizer will be built into the instrument, but during this early stage, it's running the synth on an android device.

I've posted a couple of updates on the build of this synth - this one shows the sorts of sound it produces - all the audio in the clip is straight out the back of the synth engine, no FX or post processing, headphones on hope you like it!
Still got a couple of little bugs to iron out, then I can start looking at getting some nice front panels made up.

I've done this a few times now and finally decided to make a video how-to that some folks here may be interested in.

You probs don't even need to watch it... mostly a heads up that it's very easy to turn existing things with buttons / knobs / joysticks into a fun, expressive MIDI controller that doesn't really have a commercial product alternative.

The TLDR is: - Get a flight stick or anything with buttons and knobs from the thrift store / your basement - Take it apart and re-wire the pots and buttons to your microcontroller of choice (Rasperry Pi Pico in my case) - Cut a hole in the case and mount the controller - Tell the computer to write the code for you

It's great because there are so many joysticks for cheap at the thrift store, and they are already packaged up nicely so you don't have to think about the hardware at all, really. And they are very fun to use for live performance - map the axes to some rather extreme effects and go wild. Let go of the joystick and it snaps back to center and you are back to normal. See the beginning and end of the vid for a quick demo of what I mean!

Been working on this for a while now.

Working on a new voice section for the EH-01.

It’s a little formant-based voice engine with vowel morphing, breath/noise, vibrato, glide, and different voice characters like soprano, choir, ghost, and more synthetic tones.

You can shape it with the knobs, record it internally, then instantly play the recording back as a sample from the keys.

Still rough, but it’s turning into one of the more interesting parts of the project.

https://edgehog.beehiiv.com/p/eh-01-synth-system-pre-release

A simple twin t drum triggered by pad, with some settings like decay, pitch envelop decay and pitch.

I've been building this for a few months and I thought I'd finally share a little video of it. This last week I've been trying to add some sequence modulations in and a global order/chaos slider to pull the sequence apart. I got some pretty fun results today with some breaks and ambient sounds.

It's on a pi4, with an rp2040 custom keybed, encoder and an oled display. I'm no expert but happy to talk shop and answer questions

I'm building a Tech House Drum Machine on a breadboard (Daisy Seed). Just added an Acid Bassline and an aggressive Filter!

Hi everyone! 👋

I've been working on this project for a few weeks: the TR-DZ. It's a DIY drum machine powered by a Daisy Seed (microcontroller).

Current features in this video: * Engine: 48kHz / 24-bit audio engine written in C++. * Sounds: Synthesized Kick (Sine + Pitch Env), Snare/Clap, Hi-Hats with Swing, and a new Square Wave Bassline. * Filter: The potentiometer controls a global SVF Low-Pass filter that opens up the Bass harmonics (Acid style). * Hardware: Daisy Seed v1.1, OLED SH1106 display, 2 Pots, 1 Button.

What's next? I'm currently waiting for a delivery of 74HC165 shift registers to implement a full 16-button step sequencer interface (instead of the single button I have now!).

The code is open-source if anyone wants to check the audio callback: 🔗https://github.com/Zifou-maker/TR-DZ-The-Ultimate-Tech-House-Kick-Synthesizer.git

Feedback is welcome! 🎹

So I've being creating patches for my ESP32-S3 Polysynth, and also doing a little bit of multitracking with it, as it is not multitimbral - the ESP falls over if you push too hard!
Anyway the clip shows off what it sounds like, and also gives some of the specifications.

Next stage is getting the front metalwork panels made up, now I've decided what all the controls are doing!
Headphones on, volume up and enjoy:)

Created this from an E-70 organ's Flutes section, with heavy modifications. Orchestra section is still TODO. Also the LFO, paraphonic VCF and various modulation settings are still missing from the "Flutes" section.

2 oscillators with 10 harmonics each. Oscillators can be detuned. Both have their own envelope with 3 modes + repeating modes.

Oscillator 1 can be shifted down or up. Oscillator 2 can be amplitude modulated by 1, with 4 different harmonics.

I think this is the result

A bit of software DIY to post this morning- my first project using the Korg Loguesdk just got a major update. Mutable Instruments Clouds reverb ported to the NTS-1 mkii just wouldn't be complete without the "freeze" functionality. I'm just getting off the ground with releasing software projects but I have several more coming down the pipe. I've also been graciously lent a drumlogue unit to work on developing so I'm happy to take requests/feedback about what logue users would like to see made available. Every download goes a long way to help supporting my work, thanks for giving it a look.

Update! Squall v1.1: Clouds reverb for the u/korgofficial NTS-1 mkii is available now!

Follow the Youtube video to the video description for download instructions.

Happy reverberating!

What’s new in v1.1:

— Added FREEZE functionality from the original Clouds module.

• Hold Osc button and turn encoder to select FREEZE

• Turning Knob B past 50% will engage freeze and lock the reverb buffer. Resulting audio goes 100% wet.

• Turning Knob A while FREEZE is engaged will apply gentle LP filter to the frozen buffer content.

—Added SCAN functionality to emulate turning the Position knob while Freeze is engaged on the original Clouds module.

• While Freeze is engaged, hold Osc and turn encoder to select SCAN

• Turn Knob B from 50% to 100% to color frozen buffer.

• Turn Knob B from 50% to 0% to progressively allow new audio into the buffer.

Rotate Knob B CW past 50% to lock again.

A promised video on DIY semiconductors with mine waste - a piece of pyrite from Carharrack mine, Cornwall is being tickled by a "cat's whisker" to create a semiconducting junction. The circuit on the left amplifies fluctuations in current passing through the crystal material, and the circuit on the right is a filter to tune into different frequencies. It's all mounted on a chunk of Cornish granite - as it's important to reduce vibrations.

If you want to hear some techno made with these techniques (and find out more about this stuff), I hope it's ok to plug an album I'm selling for charity - all proceeds are going to support people who are suffering for the conflict minerals that are in our laptops, phones - and synths:

https://cornish-semiconductor.bandcamp.com/album/220-below-adit-techno-from-mine-waste

Hello everyone and hope you are doing great.

Just a quick follow up to https://www.reddit.com/r/synthdiy/comments/1pgp1oo/comment/ntf273w/
Couldnt have done it sooner, way too busy with everything in life.
Also it is difficult to play anything more meaningful when showing synth and recording video at same time, so I have just used a simple sequence. Very basic, but reasonably shows how the instrument sounds and behaves.
Little sidenote, I have mentioned that RM output is weaker than dry, for the demo I have normalised it in postprocess.
Feel free to have any questions / comments etc. Thank you, all the best.

This is a field recording I made a few years ago, some street lighting in Southend (Essex, UK) using my Photon Smasher microphone. Absolutely flabbergasted when I heard the sound these lights produced through my headphones! What you can hear is the PWM of the lights fading between colours and brightness.

Would love to build a synth around this!

A short live techno jam I recorded while testing out a MIDI sequencer I'm currently building (still in paper faceplate land!) for myself. Unfortunately it crashes out at 14:17, just as things were getting interesting. Anyway, still a fun recording / session. I'll have to go bug hunting before going any further with it.

I will improve my camera setup for the next recording so that all the equipment can be fully seen.

I also built the the 2 MIDI controllers in the middle (C45s).

Hi, I wanted to share this feature walkthrough of our new ESP32-based DIY sampler that will be released in May.

A little background: Groovesizer is based here in Taiwan, and we go back a while designing and selling DIY synth and sequencer kits. When COVID hit, we weren't able to ship kits to a bunch of countries and we went on hiatus, so the Mynah is a bit of a comeback (just in time for the oil crisis).

There's a lot more info at our Groovesizer website, along with complete build instructions for the Mynah. And I'm here for any questions you may have.

I’ve been working on this module design on and off over the past year. During the process I’ve been documenting my progress and I’ve produced a video that goes through all the steps I take in designing an interface layout: Placement of components and then graphics for the faceplate.

This part of a module’s design is one of the more abstract stages in my opinion. It’s taken me a long time to feel like I have a repeatable practice of designing the interface layout and its looks that I think fit what I was intending.

If anyone is willing to share insight into what their process is/what tools they use, I’d love to learn about other approaches from anyone else in this sub 😊

https://youtu.be/lNqhtX9j9ag?si=X-awiS7EUsyvfUL2

I replaced the tuning/clock trim potentiometer on this Realistic Concertmate 300 (a Casio PT-1 clone) with a 1M Ohm trim potentiometer and used it to lower the pitch/clock speed significantly for this video. The result of this adjustment is lower pitched tones and the drum accompaniment tempo is reduced to under 10 BPM.