AMYboard: A $29.90 Programmable Eurorack Module

As a writer and synth-tinkerer, I'm always on the look out for cool gimzos and doohickeys - and one that recently caught my eye is the AMYboard. The concept; an ESP32-based module, programmable in Python, is a sound one. The AMYboard is in good company here - standing alongside other open-source and commercial projects that embrace that tinkerer's spirit. What really shocked me was the price, $29.90 for a Eurorack module that can run all sorts of cool synths, samplers and FX? I had to know more! Thankfully Brian - one of AMYboard's two developers, graciously agreed to answer my questions.

Hi Brian and thanks for speaking to us! So for the uninitiated, could you please give us a brief introduction to AMYboard?

AMYboard is a US$29 programmable synthesizer and effects unit. It fits in and can be powered by a eurorack modular case if you have one (10HP) but you can use it standalone. Out of the box it runs our firmware which lets you make synths in MicroPython and set up the AMYboard from our website at https://amyboard.com/editor (you can also simulate an AMYboard there too if you don't have one yet.) AMYboard is powered by AMY, our synthesis engine that we (myself and DAn Ellis) have been working on since 2021 or so.

What's your background, are you a long time synth/tech tinkerer or is this a recently discovered passion?

I am a scientist and startup person and have done music stuff most of my career. I co-founded a company called The Echo Nest out of my PhD work at MIT, which ended up powering a wide swath of the data layer for the music industry for a while and then was acquired by Spotify in 2014. I've since done a lot of work with privacy, recommenders, machine learning and the news. AMY's other developer is DAn Ellis, who is a close friend and well known audio scientist that works at Google on AI/ML for audio, music and speech. AMY, Alles, Tulip, AMYboard are all "side projects" for DAn and I. We love working on them and love seeing what people make with them. I've personally been tinkering with small devices and music tech most of my life and am privileged to now have the resources and time to make real "products" out of them. We're just getting started!

Tulip: https://tulip.computer/

AMY: https://github.com/shorepine/amy

What inspired the creation of AMYboard, had you experienced any other re-programmable modules or products, or was it simply the thrill of a technical challenge?

We were seeing people make amazing synths with AMY like the Spark or Diapasonix and wanted a "reference hardware" for AMY that showed off all its capabilities without any setup. Also, my brother, Keith Fullerton Whitman, is a big name in the modular world and I was always so aghast at how much these things cost! I was joking with him that we could replace much of his complex rack that probably is worth a sportscar with a few AMYboards. So we partnered with our friends at Makerfabs, who helped me build Tulip, to find a way to get a high quality but inexpensive set of components that kept the price down but the features up. It took over a year -- getting the 3 power supplies right was the biggest challenge. Everything is open source including schematics, so we're hoping others can learn from us.

Spark: https://www.youtube.com/watch?v=VHB0kLcmQHg

Diapasonix: https://www.youtube.com/watch?v=DMDRZ1dwdG4

KFW's modular setup: https://modulargrid.net/e/racks/view/3138110

The open source nature of your projects is a really noble goal! Actually, I just played with AMY's default wavetable synth in my browser (as of course,  you offer an online emulated version) - it sounds great, and I liked that you could use PCM as an LFO! If I, as a total coding n00b (I know 1982 ZX BASIC and that's it!) wanted to mess about with the parameter ranges of that existing synth, probably breaking it (but learning something!) in the process, how hard would it be?

It is our dream that people like you can do exactly that. We provide a Micropython interpreter built into AMYboard. It's quite like BASIC! And AMY, the synth engine, is directly controllable, down to each parameters of each oscillator, from Python, or many other methods (like Arduino, or SYSEX, or MIDI). We have various tutorials and docs available but know most of our work in front of us is getting more people like you to build and share their setups!

So $29.99 is crazy inexpensive for such a powerful little module! And fully assembled too right? Tell me how that's even possible?

We're using a few year old "IOT" microcontroller, an ESP32-S3, as the heart of AMYboard. DAn spent a good year of his life getting AMY to run quickly on this chip, with 8 voice polyphony for Juno-6 style analog voices (with filters and EQ.) It was a lot of hand tuned fixed-point DSP. Luckily, he's a world expert in this stuff and I goaded him into doing it for free. (He had a great time.) The rest of the components are popular and cheap and at the scale that our supplier Makerfabs runs at, they're able to dramatically cut costs. I will say that as of today we're still in the hole on AMYboard - we put some cash up front to pay for design and fabrication help, and we make a few bucks per board to pay that back. So please buy a few if you can, and once we recoup our costs we'll put the following profit into our next synth!

I'm sure it will be popular; I see that some of the cost is offset by making parts of the module optional - so, you receive the assembled mainboard with jacks, and a Eurorack panel, but then you can buy and add your own screen or bank of knobs? This is a fantastic approach I feel, as it allows people to grow their system over time - what gave you the idea?

We found that people in this world (DIY synths) always have their own vision of what they want to see for their synth. Any decision we would make, like a display size, or a controller knob, may be the wrong one for them. So we whittled down AMYboard to just the basic stuff anyone can build from - but we wanted it to work out of the box. Our closest inspiration is the Daisy Seed platform, but it doesn't come out of the box with jacks and requires a bit more setup to use as a synth. Lots of people that make great music aren't handy with soldering irons or code!

Daisy Seed: https://electro-smith.com/products/daisy-seed

Talking of code, could you tell us about 2 or 3 cool instruments/effects that people have made for AMYboard so far? I see a fair few available in the browser version.

My favorites right now:

• Dan and I made a house track with generative chord changes. The fun bit was getting the Derrick May "WOODPIANO" FM bassline just right. https://www.amyboard.com/editor/?mode=simulate&env=house_generator&user=shorepine&tab=code
• Another user made a great Techno Generator: https://www.amyboard.com/editor/?mode=simulate&env=techno_generator&user=jm&tab=code
• Our friend Douglas ported his SineClock (which tells you the time with beating sine waves) to AMYboard, including using the wifi chip to know what time it is: https://www.amyboard.com/editor/?mode=simulate&env=sineclock&user=shorepine&tab=code

Wow, quite a variety of uses there! So where can folks buy an AMYboard, or find out more information; there's a Discord right?

Buy an AMYboard or three at https://amyboard.com/

Discord: https://discord.com/invite/TzBFkUb8pG

Thanks for chatting to us Brian, and best of luck with AMYboard!