DaisySP VS Audio

You are about to bite off a lot. Ignore all the other advice in this thread, I do this for a living.

You have some software experience, this is good. Assuming you have embedded software experience (which is essential for what you are doing and not at all like web programming) you have a foothold to finish this project without going completely insane.

Hardware is a completely different beast. With software everything happens in your head and when you get stuck you can usually think your way out of it. With hardware, you really do need to learn to do things meticulously and step by step. There are many things that can go wrong. You will learn a lot on this journey.

Don't be afraid to ask for help. Finding a hardware community will be essential to do this as you learn the skills you need. You're going to make a lot of mistakes, best to go in embracing it

A good place to start is to join an open source community for MIDI. Two off the top of my head is http://www.ucapps.de/ for MIDI specific hardware and https://www.electro-smith.com/daisy

A large amount of the work you will find yourself doing at the beginning is just figuring out where and who to ask questions about things like the keybed and other hardware issues. None of this is terribly 'hard' but none of it is easy. Most of it comes from experience.

It is almost always best to use someone else's product when you are designing your first. Roger Linn (https://www.rogerlinndesign.com/) gave me some fantastic advice a couple years ago when I was trying to design switch caps: "Do you want to be a company that designs switch caps or one that designs synthesizers?" and that stuck. I don't want to design switch caps, so I bought them off the shelf, contracted someone to design my own, and moved on.

So to that end... just buy a couple keybeds from Fatar or someone else, or just grab a synth you already have or buy one off ebay and harvest the keybed from that (often times much cheaper than buying direct!)

Don't be afraid to spend money on tools. If you find something difficult, like soldering, I have not once regretted spending money on better tools. They grow with you and save you hundreds if not thousands of hours of unnecessary frustration. When you know you need a tool, find a way to get it.

Maybe I should make a blog post about this... hmm

Hope that helps!

Check out Daisy DSP from ElectroSmith. They have an entire platform you can build your own synth upon. Many new EuroRack modules being released over the last ~1.5 years are built upon the Daisy SDK.

Here is the GitHub https://github.com/electro-smith/DaisySP

For an excellent implementation of C++ embedded audio DSP, checkout the DaisySP project and associated hardware. The libDaisy audio drivers abstract this block processing well.

There is a github page for this that has downloadable firmware and a link to the firmware programmer which suggests that it’s running on a Daisy. Although it would be ethically super questionable at best, it probably wouldn’t be that hard to reverse engineer.

Teensy which gives you a lot of options with its audio library and GUI tool.

Teensy is more powerful than Arduino, 4.X boards are in stock, 8 sets of serial ports, and has a supported audio library

Just in case you don't want to go from low level code and up this is the library development version (there is a release version that you install into the Arduino environment as well) and this is the GUI that makes it simpler to do the layout work for the modules of your device to make it more straight forward to do the build of the design work. You drag the modules from the left into the work area and then connect them up. Once you have the layout you want you then export the code for it into the Arduino IDE. In the right hand panel is the description of each module and what commands are used for it in the IDE.

If you are targetting microprocessors, you are probably best coding it from scratch so you can optimise. Teensy 4 seems to be the platform of choice for a lot of synth projects. The Teensy Audio Library might give you a bit of a head start. Dexed-micro touch is a great open project that can give you an idea of what is possible on Teensy and the dev is quite approachable.

You can overcome the RPi scarcity by migrating the code to the Teensy platform, which aside being cheaper and less power hungry than the 2,3,4 RPi, is a lot cheaper and more easily available. Not an easy task since there's no Linux under the hood, but there are some excellent audio/midi libraries to help. They already built commercial-level synthesizers with it. By combining the breath sensor data with other pressure sensors you could end up with a very expressive instrument.

https://www.pjrc.com/teensy/index.html

https://www.pjrc.com/teensy/td_libs_Audio.html

https://www.pjrc.com/teensy/td_libs_MIDI.html

https://www.youtube.com/watch?v=z2674LdYW5I

Personally, if I need to make custom software modules and design my own PCBs, I'm almost certainly not going to use something like LightShowPi as my starting code. I'd probably use a Teensy + Audio Shield + EL Sequencer and have the Teensy Audio Library do all the FFT/beat detection. It'd be much more power efficient, easier (IMHO) to build and maintain, and it still allows for expansion options for future add-ons. Funny thing is, I actually own an El Escudo Dos, but I have found it to be a giant PITA compared to simple edge-lit "Neon" LED strips or even the newer "nOOds" from Adafruit.

> Silly question but why is the Pi necessary?

Not sure about this project, but generally it is not. All it needs is a small board capable of running Linux and the necessary drivers for external ADCs/DACs where necessary, plus the digital fx software. As an example, Guitarix runs also on ARM and can work on cheaper boards such as the Orange PI, Nano PI and many others cheaper and more obtanium than the Raspberry PI. https://guitarix.org/

In some cases you don't even need to run Linux. There are many effects projects using a cheap Teensy board plus its piggybacked audio card; it features a really powerful audio library and is compatible with the Arduino IDE.

https://www.pjrc.com/teensy/

https://www.pjrc.com/teensy/td_libs_Audio.html

The Teensy is truly amazing, to the point one can build synthesizers that just a few years ago would cost hundreds of bucks. Take a look for example at the TSynth, 100% Open Hardware & Open Source, also available in kit.

https://electrotechnique.cc/

Demo here: https://www.youtube.com/watch?v=uCA2L7CeWSE