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by woudsma 1205 days ago
Very cool, I've ordered a Raspberry Pi touchscreen this weekend and it should arrive today. I want to make a MIDI sequencer with it, or at least play with the idea. I hope my old Raspberry Pi can work with MIDI (over USB) without too much latency..
3 comments

Depends on how you want to utilize it. If you want to connect it to a computer as a MIDI device, you'll have to use an Rpi4 or one of the Pi Zero's. The Pi's < 4 can't go into "gadget mode". I bought a new v4 for this exact reason.

The RtMidi library is probably your best bet for getting started. I found the ALSA library to suit my workflow a bit better, but the setup is pretty obtuse. RtMidi is much more user friendly in that regard.

Also, look into implementing the Ableton Link library. It runs over your network, and is honestly astounding how well it sync's devices.

Ideally I'd sync it with Ableton's clock. I'm using Ableton only for tempo and multitrack recording. Maybe this is achievable without the RPi being a MIDI device? Sending messages over the network, like GuitarEffects which uses WebSockets. My RPi 2 doesn't support gadget mode (I should probably start looking for a RPi 4).

I'm currently using an Elektron Digitakt to sequence my analog gear - it's great - but unfortunately the DT is limited to 8 MIDI tracks with only 1 LFO per MIDI track to automate MIDI CC data. I'd love a Cirklon Sequentix but the waitlist is just too long (3 years atm, arghh).

I wonder if I can hook up something like a Midiface 16x16 (https://miditech.de/en/portfolio/midiface-16x16/) to the RPi. The Midiface is Class Compliant so maybe the RPi can use it natively..(?) I'm a bit worried about performance though.

Thanks for your suggestions, I'm going to look into them!

Can you readily get an rpi4 anywhere?

The Odroid C4 you can actually get is an alternative with 4 USB ports and an OTG that is gadget capable. Unlike older models, mainline Linux support is decent.

I’d say you can most definitely do that. You can get usb midi conversion cables for next to nothing and send an out signal to a midi hub or Daisy chain it. Midi is a seriously slow protocol so as long as the actual audio processing is happening on other devices and you’re just sending midi to them, you’re definitely good to go.
I've seen it done with the Pico, where it acts as a midi device when plugged in to a host machine; not so sure about the main boards.
The pi zero hardware supports gadget mode and from there it's a bit more work to get it to enumerate as a midi device. The pi 4 supports this via the usb-c port.

https://raspberrypi.stackexchange.com/questions/71613/how-to...