/r/synthdiy

Photograph via snooOG

building, modifying and repairing synthesizers


rules:

1. No transphobia, racism, or bigotry of any kind.

2. Try to keep it on topic.

3. It’s chill to share and sell your work here, but (a) it has to be DIY-related—something that other users can build or use to build—and (b) you have to make an effort to be a human being participating in a community, and not just a marketing account. Moderators’ call on that one.


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/r/synthdiy

50,584 Subscribers

2

SUPER CHEAP Blowout of Power Distribution Boards

2 Comments
2024/12/03
23:40 UTC

2

I made a 30hp Eurorack breadboard companion, Then I jammed :)

0 Comments
2024/12/03
18:57 UTC

3

Beginner Looking for DIY Eurorack Module Guides

Hi everyone,
I’m a complete beginner in DIY and would love to build my first Eurorack module. Does anyone know of simple guides or projects for absolute newbies, ideally with all parts (including component names) listed? I’m looking for an easy way to get started, with clear instructions. If you have any helpful links, tips, or build guides, I’d greatly appreciate it!

Edit: I’m German-based, so a lot of websites won’t ship to me. Also, does anyone have recommendations for affordable components or suppliers?

Thanks so much in advance! 🙏

8 Comments
2024/12/03
17:57 UTC

2

LPG Using Photofet Optocouplers - Anyone have more resources regarding this?

7 Comments
2024/12/03
14:18 UTC

112

Combo Organ Synth Module

I’m a big fan of the Vox Continental and Farfisa sounds so I tried to make a synth voice to approximate that. It uses a CD4106 VCO and a divider section to get all the lower frequencies. The divider uses CD4024 counters to do the octave division and one CD4017 to get the additional harmonic frequencies. A blend control mixes the harmonics and a rotary switch selects the ratio. Another CD4106 oscillator generates the LFO for vibrato.

12 Comments
2024/12/03
03:38 UTC

3

Building a digital sampler module?

Hey all, I’ve come up with the idea to build a 12 bit 42khz digital sampler module for playing chromatic samples like you’d do on a Fairlight or Emulator. Albeit instead of floppies and images just using wav files via usb thumb drive. I have no experience with making electronics but think it would be easier than building a full sampler. Let me know what you all think or what I should do to learn how to make one.

6 Comments
2024/12/02
23:59 UTC

2

EMF shielding?

I'm starting to delve into DIY synth having built a bunch of guitar pedals already. In the guitar world, we're often concerned with ensuring there is a Faraday cage around our circuit (usually accomplished with a grounded metal enclosure, but could be foil, etc.).

As I'm looking over synth modules, it doesn't seems to be as big a deal. I'm guessing it's because guitar signals are weak and we often use high gain for distortion, whereas synth oscillators have more voltage to start with, and the circuits tend to be less "gainy". Is that right, or is there something else I'm missing?

11 Comments
2024/12/02
17:34 UTC

2

looking for recommendations :)

hi!! my boyfriend is an incredible and very curious musician who recently got a soldering iron and has expressed lots of interest in "diy kits"

I'd like to get him one for his birthday, what are good places to start that are cheap? Good online stores to purchase from /links would be incredibly helpful! thanks so much :)

edit: will be shipping to canada!

7 Comments
2024/12/02
13:13 UTC

1

Still struggling about the 4-operator registry in Yamaha YMF262

If I'm about to use 4-operator mode, should i write the KON register on both array? Or the otherwise? And what does FNUM LSB even mean?

2 Comments
2024/12/02
06:02 UTC

2

Looking for a MB6582 panel as a pcb

Hi All, I found this forum http://midibox.org/forums/topic/21320-mb-6582-panel-check/ and see that some others have done the heavy work of designing PCB panels for the MB-6582. I would like to hopefully be able to get one made as well. Anyone have a source for these?

10 Comments
2024/12/02
04:40 UTC

1

Is the Midibox.org forums functional?

I tried signing up for an account a couple weeks ago and was waiting for the final approval email, but when I tried logging in to check, i get the message that I've been banned. The contact form is also very generic.

2 Comments
2024/12/02
04:05 UTC

4

Looking for a good drum machine kit.

Anyone know of a good Drum machine kit? I would like something that could sync with my modular using a clock in.

15 Comments
2024/12/02
00:24 UTC

2

[Norns without shield] K1/2/3 & E1/2/3 emulatio

Hi guys! Sorry for my english, frenchie here So I shelved out a raspi4b and built Norns on it, but i don't have a shield, just a scarlet 2i2

I just diyed a midi controller with an Arduino and I want to replicate K1/2/3&E1/2/3 behavior with it and I thought that was pure midi mapping but it seems i were wrong.

Unfortunately my keyboard won't allow to do changes in matron's script interface -F1/2/3/4 and arrows work in the menu, so I can navigate- means I'm stuck with default settings when I launch scripts, sad. I can't even reset the script, I have to go in maiden to ;restart... Maybe I'm dumb and I didn't found the way to do it with a keyboard I just managed to plug an old mpk mini and send midi notes/CC to play around (Norns kills... dayum this is so good) but not much luck

Do you know by any chance if there is a midi solution to replicate the shield's encoders/knobs? Many thanks in advance for your insights !

2 Comments
2024/12/02
00:20 UTC

1

SMD led question

I'm looking to modify a little gadget synth and stick it in a normal size box with large pots, switches and buttons. If I remove the tiny SMD LEDs would wiring a through hole to its place work out? Provided the color is the same? Thanks!!

2 Comments
2024/12/01
20:46 UTC

137

New demo track on my open-source pocket groovebox

21 Comments
2024/12/01
19:56 UTC

3

How to wire jack switch for the Arduino to detect if it's in use?

https://imgur.com/a/r1FHMn8

I am using the above input circuit to send a clock signal from jack "CLK_jk" into Arduino pin "CLK_in". I'd like the Arduino to know when the jack is not in use, so it can create its own clock. I tried to wire the jack's switch lug to a spare arduino input "jack_detect", but the jack_detect pin tends to float when its not grounded (ie when the jack is in use). I can't figure out a pull up or switch arrangement that doesn't effect the "CLK_in" pin.

Do you guys have any examples I could imitate? Any input is appreciated.

9 Comments
2024/12/01
19:33 UTC

2

Question about microcontrollers controlling a synth voices

If I want to use a microcontroller to control a DCO synth voice, how many output lines do I need per voice? I know I'll need signals for gate, velocity, and frequency. Is there a way to combine gate and velocity into a single line, or do they need separate outputs? What's the most practical approach?

11 Comments
2024/12/01
17:17 UTC

3

Open source audio prototype boards [feedback wanted]

2 Comments
2024/12/01
11:58 UTC

4

Audio signal over IDC ribbon good/bad/ugly?

Is transferring audio over 2.54mm flat IDC ribbon cable going to introduce noise? What about if I put a ground on either end or something?

For context the two places I'm thinking to use it are, about 20cm in a plastic casio keyboard - from a PCB (direct solder) to a PCB (using a connector) and from a PCB (main board) to PCB (daughter board with pots/audio in/out) with connectors, maybe only 5cm. Again in a plastic casio where there is a little bit of aluminium cardboard for shielding.

I just find them so neat, and easy to make. I've been using a G clamp and slowly tightening it. I know others use a vice, but this works for me.

10 Comments
2024/12/01
00:36 UTC

11

Felt like trying out some chill House vibes, kind of dig it

4 Comments
2024/11/30
19:03 UTC

1

Casio CZ3000 parts (Chorus Sliding Pot)

Hey All,

Any recommendations for places/parts I can use for the sliding chorus pot on a casio CZ3000? I'm in the UK!

If anyone knows a part number I'd be super grateful

2 Comments
2024/11/30
12:24 UTC

2

Latest work on my DIY synth engine "exsynthia"...

This video shows PCM file loading along with tricks of lowering the quality of the playback and modulating them with the built-in single-cycle waveforms.

https://youtu.be/PHGQqivtu94

In a few days, I'll share a presentation of this mess at the Nerves/Elixir meetup.

0 Comments
2024/11/30
02:30 UTC

81

I've spent the last 3 years building a free tool to make DIY audio building a bit easier. I'm finally ready for some beta test users to check it out!

TL;DR:

BOM Squad (https://bom-squad.com/) is a free, open-source tool I’ve been building for the past three years to make DIY synth-building easier and less frustrating.

Summary of key features (7 minutes): https://youtu.be/ddtQrfLwvgs

It’s still in beta testing, so expect bugs and changes as we improve things. BOM Squad is open-source (Django, React, TypeScript, PostgreSQL, Docker) and perfect for first-time contributors. Check out the GitHub or watch one of the videos for more details:

Wall of text…:

Hey DIY audio hardware folks! Hope you had a great Thanksgiving if you celebrate it!

I’m super excited (and a little nervous) to finally share BOM Squad, a free tool I’ve been slowly and not-so steadily building for the past three years. It’s an open-source web tool I built to solve the frustrations I faced when I got into DIY synth building during the pandemic. If you’ve ever been overwhelmed reading a manufacturer datasheet or remember how hard it was to put together a BOM during the pandemic, this tool is dedicated to you.

Here’s how it started: back in 2020, like a lot of people, I suddenly had a lot more time at home. I decided to dive into DIY audio hardware, starting with Nonlinearcircuits Eurorack modules. I learned to solder, built a few kits, and then rapidly got frustrated by how opaque the whole semiconductor industry felt to me as a beginner.

Every build came with a BOM—a long list of components I needed to source. If I was working on multiple projects, I’d copy everything into a spreadsheet to figure out which components overlapped so I could save on shipping. People share spreadsheets, but it’s the wild west out there, with little standardization of notation. I’d spend hours sorting through supplier websites trying to figure out which ICs to buy, only to find out that some components were out of stock or discontinued, or there were multiple options I didn’t fully understand. On top of that, keeping track of my personal inventory—what I had, where I stored it, and how much was left—was a nightmare.

My background is in software development (I also have two degrees in music), so I started building a tool to make the process easier. After a couple false starts, that tool became BOM Squad. It’s meant to be the kind of thing I wish I’d had when I was starting out: an interactive, community-driven app that simplifies sourcing components, managing inventory, and organizing your builds.

So far I’ve gotten enthusiastic support for both initial users and manufacturers. All manufacturers on the site are there because they wanted their modules listed. I plan to add DIY guitar pedals and other types of DIY audio projects over time.

Here’s what it does:

  • Interactive BOMs: Forget static spreadsheets. BOM Squad turns manufacturer BOMs into actionable lists with links to suppliers like Mouser, Tayda, and DigiKey. You can compare components, get recommendations, and even see reviews from other users about what works best for specific builds. If you choose to use the inventory feature, the BOM itself is aware of your inventory and cross checks components against what you already have.
  • Inventory Management: You can track your components down to the exact shelf or box (think: “Closet -> Box 6 -> Cell E4”). BOM Squad cross-references your inventory with your BOMs, so you’ll always know what you already have and what you still need. It also logs all changes in Inventory Version History, so you can undo mistakes if needed. And yes, there’s a BIG TEXT and dark mode for late-night soldering sessions. :)
  • Quick Export: If you don’t want to use the inventory feature, that’s fine! BOM Squad lets you export BOMs directly into formats compatible with supplier upload tools like Mouser, DigiKey, or TME. So you can create a cart on a supplier website directly from the interactive BOM. This makes it super easy to populate shopping carts and skip the manual entry.
  • Custom components and suggestions: You can add your own components to the database if they’re not already listed (this feature is currently in development and is changing fast from day to day). A new feature we’re adding soon is the ability for users to attach suggested components to BOM items. This will make it easier to find substitutes for discontinued parts or get recommendations from other users.
  • Consolidated Shopping Lists: If you’re juggling multiple builds, BOM Squad groups all the components you need by supplier, calculates costs, and helps you avoid over-ordering. It even lets you save and reuse shopping lists for recurring builds. 
  • Community Knowledge: BOM Squad is designed to be a hub for the DIY synth community. Users can leave comments on components, modules, or builds, sharing insights and tips. You can also see how frequently certain components are used across different projects, which can help with planning and sourcing.

This has been a labor of love for the past three years. I’ve built it in my spare time while balancing a full-time job, a growing family (my wife and I had a daughter during this time!), and my passion for music and coding. BOM Squad is free to use and open-source. If you have a background in software, whether you’re an experienced engineer or new grad, we’d love to have your help with the project over on GitHub. It’s actually the perfect first contribution to open source, because I’m still trying to figure everything out myself. :) It’s built with Django, React, TypeScript, React Query, React Hook Form, Tailwind, PostgreSQL, and Docker, so it’s a great opportunity for anyone looking to get into open-source development.

Feel free to create an account and check it out, but please remember this tool is still in beta test mode! Things will change rapidly for the foreseeable future and there are still lots of bugs and stuff is rough around the edges still. I would love any and all feedback, and bugs can be reported either via opening an issue on GitHub or through the “Report a bug” button you see on some pages of the site.

In case you’re looking to dive deeper, I made a couple videos outlining key features, although the videos are already out of date with regard to the feature set that’s currently there:

Summary of key features (7 minutes): https://youtu.be/ddtQrfLwvgs

Full video: https://youtu.be/7cbePdMJsms

This has been a super rewarding project to work on, including a lot of feedback I’ve already gotten from the Nonlinearcircuits community over on Facebook, and I hope it makes DIY synth-building easier, more fun, and accessible for everyone. Let me know what you think—feedback, feature ideas, or just sharing your experience means the world. Let’s build something amazing together! 🎶

15 Comments
2024/11/30
00:26 UTC

1

Question about power supply

I’m really looking into getting a modular setup and im doing most of it myself. My only concern atp is the power supply. I’ve seen a bunch of people suggest using old PC power supplies like Meanwell’s stuff, and I was wondering if that’s a safe, reliable option. I was looking at this one in particular: https://a.co/d/fJcoUv9 . That should at least cover the +12V/-12V.

Second question, if Meanwells are a good choice, how do I connect it to a busboard so I can actually connect it to modules?

Please lmk if I got anything wrong, I’m definitely still learning.

2 Comments
2024/11/29
22:59 UTC

2

Resource for cv to usb midi

I had an idea for cv to midi conversion for a drum sampler on the laptop

Instead of continuous cv which might be inaccurate using clock signals to set midi cc values 1-127 or maybe even 14 bit cc so no need for good adc

Just count the period of the clock

Any idea how I would get started with physical components pretty good with software

12 Comments
2024/11/29
21:45 UTC

2

Is it ok to combine two 5v lines from the same power board?

Hi everyone, quick question here. My knowledge of electrical systems is average, not great, not terrible.

I recently got a Befaco Midi Thing v2 and I tried putting it in a case that does not provide 5v and the module does not power on. However, it does work in a case that provides 5v.

Now, I see that, on the back of the module, is a separate power board that outputs +12v, -7v and twice +5v (see image below). I have measured all outputs while connected and all but the top +5v give off power. So I asume that the top 5v is connected directly to the 5v from the rail, which my case is missing. The bottom +5v gives off 5v, like it should.

Is it ok to just solder a bridge between both +5v's? I quickly tried it out using the pin of my multimeter and the module seems to power up if I do. But I'm not sure if this could cause long term harm.

I'm unsure what the meaning is to have two separate 5v lines...

I *think* that it should be ok to connect them, since it seems that the top 5v line is not connected to anything, it reads 0 on the multimeter. (If it IS connected directly to the 5v rail of the case, it could cause it provide 5v to other modules, but none of my other modules seem to mind missing the 5v rail, so I assume its not that big a deal.)

What do you think?

https://preview.redd.it/kalwowfxqw3e1.png?width=680&format=png&auto=webp&s=6a141f849a1241462b27d8d0c48c0fa222fafbe3

4 Comments
2024/11/29
21:29 UTC

1

Maximum panel thickness?

I will be building a modular system in the Kosmo format. In my search for cheap panels I found some old wooden sheets. They are very sturdy, but unfortunately they are quite thick at 6mm. Would this be prohibitively thick? Are there other downsides to wooden panels that I haven't foreseen? My thanks to you.

6 Comments
2024/11/29
17:55 UTC

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