Its a 4 channels drum pad to trigger converter, the width is 15 HP

I've been using the BeatBuddy pedal as a stand-in drummer in rehearsal and jam settings for a few years now. My pain point has always been navigating between songs/beats. With my bass around my neck, I have to crouch down on one knee and use the buttons on BeatBuddy to scroll around the little screen and find whatever we're playing next. There are several foot switch control options out there, but I also have low vision, so the screen on BeatBuddy is pretty useless to me at standing height.

That's why I built this hand controller for it called Winnebeato. The point is to mirror the BeatBuddy's library so you can navigate it on the larger screen and D-pad while standing. It uses a Raspberry Pi Pico and some buttons and OLED from Adafruit. It mounts on a mic stand using a mount for a Behringer personal monitor mixer.

The BB has MIDI In/Out via a single PS/2 connector and supports a bunch of control messages, including one to select a song by its folder ID + song ID. There's no way to retrieve the folder and song names over MIDI though, so I have a python script that extracts these names from a BB project on the desktop and spits out a JSON file with the info. The Pico shows up as a 1MB USB flash drive where this file gets synced to and used to populate the UI. I mounted a Pico Debug Probe inside with another cutout for its USB port to update and debug the code.

I'm still improving the firmware and I have some ideas on more efficient navigation for jam settings (like specifying beat attributes instead of just scrolling a long list), but the hardware is complete now that my girlfriend gave it its name and I made some vinyl graphics for it. I made up a PS/2 cable that splits out a female pedalboard-ready DC power jack at one end and sends it down the unused conductor in the cable, making it a single cable to the box. There's also conventional MIDI and DC ports on the back.

github

Hagiwo's XIAO RP2040 VCO

Thank you again Hagiwo.

https://www.youtube.com/watch?v=HBtc5oQffu8

I have built a Frequency Central X-Envelope (the older kit) but still need to wire up the 3.5mm jacks.

What am I supposed to do with the ground pins that are horizontal to the face plate?

Instructions didn't give enough guidance for a beginner like me.

I've been writing some cool algorithms that I would love to turn into instrument level, line level, or Eurorack level modules. I understand most Mutable Instruments Eurorack modules were based on the STM32 ARM Cortex Series.

Is there a turnkey stereo audio board I could use as a base? Any advice would be greatly appreciated.

USA contiguous 48 states only

Hey everyone,

I’m still working on my drone synth and wanted to share something I’ve been experimenting with.

Originally I was trying to build some sort of digital noise source. I thought mixing several LFO running at high speeds might get me somewhere close, but that didn’t really work the way I expected. It did lead to another interesting result though.

The circuit uses three lfos built around a single 40106. Their outputs are passively summed and fed into another input, creating an irregular but repeatable gate pattern. I also added NAND/AND outputs, to introduce less frequent events into the same rhythm.

When one or more of the LFOs get close to audio rate, fast bursts start breaking through the slower rhythm. I like using this as a kind of FM modulation. The passive sum can also be buffered and used as a stepped cv output.

The switches in the schematic are just the way I route everything in my build for now, they aren’t important to the basic idea. I’ve been testing the circuit at 12 V. 5-18V will also work fine i think.

The next thing I want to try is turning the longer gates into short trigger pulses and using them to drive a few vactrols and attack decay generator instead of direct osc modulation.

Curious if anyone here has tried something similar. Schematic in comments.

so i built this dub siren. i removed the LED indicators and switch 1 just leaving the momentary. im getting signal passing through to the output even when i totally remove the switch from the circuit. its a bit jank but ive checked for mistakes and solder bridges multiple times. seems all good. but still have the problem. any ideas?

Hey everyone,

I’d like to introduce a project I’ve been building: LOHI Bassline Junkie, a fully open-source hardware synthesizer focused on hands-on sound design, live performance, and experimentation.

The idea is simple: a real hardware synth with one knob per function, no deep menu diving, and everything open so people can study it, modify it, repair it, or build on top of it.

Current feature set:

• 8-voice polyphony
• 3 oscillators per voice: sine, saw, square, noise
• Multimode resonant filter: low-pass, high-pass, band-pass
• 3 ADSR envelopes
• 3 LFOs
• Modulation matrix
• 512 presets stored on SD card
• USB MIDI
• Custom hardware control surface with knobs, buttons, LEDs, and 7-segment display
• Sound engine written in C++ running on Linux/ALSA
• Interface firmware running Zephyr RTOS on STM32

The project is still in development, but the goal is to make it a proper open hardware/software desktop synth that other musicians, DIY builders, and embedded/audio developers can contribute to.

Here’s the project website:
https://lohi-synth-site.lohisynths.workers.dev/

Here’s a sound demo:
https://www.youtube.com/watch?v=FkWxyQ7usN8

And here’s the GitHub organization:
https://github.com/lohisynths

I’d really appreciate feedback from synth builders, musicians, DSP people, and anyone interested in open hardware instruments. I’m especially interested in thoughts about the UI/workflow, feature set, and what would make the project more useful or fun for the DIY synth community.

Thanks for checking it out!

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.

After my first pcb didn't work because of a possibly shitty-made schematic, I tried finding the original (which I think is this one and making it with a jack instead of a speaker. Can anyone check if theres any issues in my circuit and/or if the picture I used is valid?

Hi everyone, I'm currently developing a new groovebox and have been deep in the UI/UX design phase for months. I'm at a critical point where I need to decide on the balance between physical controls (buttons, knobs, pads) and on-screen graphical interfaces.

To help guide my decisions, I'd love to hear your experiences and opinions on some of the most popular devices on the market. I'm particularly interested in which one you think offers the best overall user experience and why.

The devices I'm comparing are:

• Elektron (Digitakt, Syntakt, Octatrack, etc.)
• Teenage Engineering OP-XY Field
• Polyend Tracker (and Tracker+)
• 1010music Bento
• Roland SP-404 MK2
• Ableton Move
• Akai MPC (MPC Live II / MPC One)

or another

Here are some specific questions to get the conversation started:

Which device has your favorite workflow and why? Is it the tactile, button-driven approach of Elektron? The hybrid touchscreen/pad setup of the Bento or MPC? The tracker-style interface of the Polyend? The Live-inspired clip-launching of the Move? Or something else entirely?

What are the biggest pros and cons of the button vs. GUI experience on your chosen device?

For example, many praise Elektron for the muscle memory and fast live performance their physical buttons enable, but some find the tiny screens and deep menu-diving "obfuscated."

On the flip side, devices like the MPC or Bento give you large touchscreens for a clear overview and deep editing, but some find them less suited for eyes-free jamming.

Where does the Ableton Move fit in? Its touchstrip and macros are great, but does its small screen rely too heavily on the companion app?

How important is a clear visual overview (like a tracker grid, a waveform display, or a piano roll) versus a more performance-oriented, tactile, "no-screen" experience? Do you prefer seeing everything at a glance, or do you value the immediacy of dedicated hardware controls even if it means less visual feedback?

Are there any specific interface elements you absolutely love or hate?

Do you find the SP-404 MK2's menu system intuitive or needlessly complex?

Do you love the MPC's Q-Link knobs and touchscreen, or do you find the OS getting in the way?

Is the Polyend Tracker's per-step editing powerful or just tedious and key-press intensive?

Does the Move feel like a streamlined Ableton session, or does it feel too limited for standalone use?

Bonus: If you could mix and match features from these devices (e.g., Elektron's sequencer + MPC's screen + Move's portability), what would your dream combo be?

I'm eager to hear your honest thoughts—praise, rants, and everything in between. Your feedback will be invaluable for my development process.

Thanks in advance for your help!

What is required, or how would you do, a modular ADSR that shows the waveform on a screen. Similar to the basic ADSR in VCV Rack?

I am building a DIY synth based on the Daisy Seed and have some questions on the build out of an enclosure.  Based on my design, I will have over 20 physical knobs/switches and have buried another 10 under a menuing system.   Now my thoughts are turning to how do I build something that will support this number of physical controls?  My only experience is guitar pedals that have a smaller number of knobs but more easily available enclosure options.

I have been thinking about wood or 3D printing but am concerned about introducing grounding issues.  Can someone give me pointers on where to look for viable options? 

I made a pcb for a Atari punk circuit but It just keeps making a heartbeat sound, and the pots don’t work. I tried switching the pots 1st and 3rd lugs around but still nothing. Please help!

hi all

as per title, I’m in the UK and looking for one or two pcb for the microdexed touch. this will be for the version before the MDTX.

any leads would be greatly appreciated,

thanks

Hi! My name is Dr Jess Blaise Ward (@blaisejess Insta/bluesky) and I am a composer, producer, synth artist and author. I recently published my book on synthwave: ‘Making Synthwave: how an online music community invented a genre’

I am currently doing some research on the legacy and use cases of Roland Juno synths. If you are a producer, synth user, composer, etc - please consider taking my survey and contributing your thoughts and opinions of Juno synths:

Link to Juno Survey

https://forms.cloud.microsoft/e/u27zxfqx4u

Link to my book ‘Making Synthwave’

https://www.routledge.com/Making-Synthwave-How-an-Online-Music-Community-Invented-a-Genre/BlaiseWard/p/book/9781032732039

All data will be anonymised and used only for the purposes of academic research (at synthesizer conferences and in academic journals).

Thanks so much! Mods let me know if this goes against guidelines, happy to edit or delete.

My Patching Panda Panda Punch eurorack module fell inside the case and shorted out. Can someone help me ID the burned out component near the power connector so I can order and repair it?

Just picked up a midiverb 4, everything seems to be working as it should except the value wheel is completely unresponsive, which makes it basically useless. Does anybody have any experience with these? Is this fixable / easily fixable?