Hey folks,
this is my first post here and I am very new to this whole topic, so bare with me. I am making music since quite a few years and have been dreaming about building my own little drum machine, to integrate all the functions I am missing with existing ones.

Recently I stumpled upon PD as a tool to realize this on the software side. While PD looks doable, even for a noob like me, I have no clue how to realize the hardware. I learned about PD through the organelle, a little synthesizer, which runs PD patches on a Raspberry Pi. (There are topics about this here, but dunno how well known it generelly is around here.) So I guessed I could do the same: Create all the Functions in PD on a Rasperry, connect the Raspberry to some knobs and buttons and then assign the Functions in my programm to those knobs and buttons.

Heres where I'm left clueless: how do I do that? I know that there are breadboards and I figured I can somehow put together a prototype on such a thing, try out different possibilities and if at some point Im satisfied think about actually building the thing. But as you probably guessed by now I have no clue neither about raspberry nor about electronics. So can anyone give me advice on how to start such a project? Or maybe tell me that my assumption is completely wrong and its way more complicated?

Hope Im in the right subforum and my question is not all to basic. Any advice would be great!
Cheers and thanks a lot!

@Herr-Rausch I would look into bela instead of a pi for this, it will be less of a learning curve, has analog inputs so you can have pressure sensitive pads or knobs without much work/hats/external mpus, active community and forum dedicated mostly to audio hardware with pd and will be about the same cost as a pi and the only decent soundcard for the pi. You can do it with a pi if you want to and some more knowledgeable folks will show up to detail that path. There is also a dedicated hardware platform for audio with a pd like interface for programming whose name is escaping me at the moment, that might be worth looking into, perhaps someone here knows it.

@Herr-Rausch +1 for bela. DMX Krew has already made a drum machine using it.
https://blog.bela.io/opal-rhythm-computer-dmx-krew/

Great advice, thank you guys! Iwill take a deeper look at Bela

I might be old fashioned, but if I were to build some rpi/whatever pocket machine to run on PD plus external hardware, I'd go out of my way to make everything midi compliant

That way I can plug in my pd running device into anything that sends/receives midi and not worry about some obscure this language/device only standards. If I want the tilting of my iSmart device to control something, having it send 14bit MIDI control signals to my sound-generating PD is no problem.

The problem with rpi is latency. which is solved by a proper soundcard + low latency kernel (dedicated soundcards + OS exist). The cost of which is....(?)

I am not trying to shill anything here and I don't know bela. But why mess around with voltage control when you can just make everything midi compliant and work cross platform/device/daw/what-have-you?

@bocanegra I think you might be confused as too what Bela is? While they do make modular front panels for their product it is just a begalbone with a custom linux tuned to our needs, a very good sound card, some easy to access (software side) digital and analog I/0 for easy interfacing with anything you want. If you already know this then I am confused as to why you are bringing up voltage control and am just guessing.

As too midi, from what I understand, Bela is already setup for USB midi but not old fashioned DIN and 1/8" MIDI. It would be fairly simple to implement old fashioned MIDI using the GPIO on either a Bela or rpi, should even be able to do it from within pd if you really wanted to, not that you should.

If there is no real reason, I would not restrict the project to a fairly slow hardware from start, - why not use the PC?

Bela has ultra-low round-trip latency on it's GPIO (3 samples I think), this can make a very responsive HID or jitter-free Midi DIN port.

@Herr-Rausch said:

dreaming about building my own little drum machine, to integrate all the functions I am missing with existing ones.

It takes some time to build what has already been done in commercial products.
Beginning with "Hello world", expect more learning-by-doing then surpassing those in their entirety.
In hardware, there are some fully-fletched open-source projects, too:
Such as LXR Drum, Midibox Seq, Elements, Rings .... you could pimp to your needs.
While learning Pd will open up possibilities.