8 knobs bank for midi control in eurorack format

[javifr]

HI!

I'm planning on building an Eurorack module for basic midi control of other modules ( such as Es-9 and Hermod )
8 knobs that send some cc messages over midi.

I have some initial ideas of how to do it but for sure I'm missing a big part of how to do it
Could someone point me out or help me? Would others be interested in something like that?

Thanks so much in advance!

Mockup

Format

• Would like to be Eurorack ( so powered by normal eurorack power )

• Size 8hp or 10hp

Features

• 8 knobs to send cc's via midi

• 1 button so i can switch between some programs ( every programa would map different cc's to the previous knobs and buttons )

• 1 jack midi out trs type b

• - Would like to be able to **easily configure which CC are mapped to every knob ( ideally web based without unracking the device )

Connectivity -> MIDI out via:

• back of module via pins

• on frontal ( trs type b ideally.. )

My main goal for this module

• Control via midi some [HERMOD](https://squarp.net/hermod/) params ( so from the type b to the midi in in hermod )

• Control via midi [ES-9](https://www.expert-sleepers.co.uk/es9.html) in standalone mode _( mainly for volume mixing duties via the back of the module )_ , here some reference to ES-9 manual:

Inspiration
Not needing the CV out control, but MIdi wise that's the inspiration

• [Tesseract Sweet sixteen](https://www.modulargrid.net/e/tesseract-modular-sweet-sixteen-alternative-silver-panel )

• [F8r](https://www.modulargrid.net/e/michigan-synth-works-f8r-)

• [16n](https://llllllll.co/t/16n-is-a-bank-of-faders-release-thread/18620/574)

• [Some livids](https://www.gear4music.es/es/PA-DJ-and-Iluminacion/OFFLINE-Livid-Instruments-Elements-Module-16K/SSY)..

BOM / build parts
I would like to understand the needed building parts, some initial approach

• The teensy ( which one? )

• 8 pots ( which type? )

• 8 knobs

• Resistors?

• A 8hp blank panel ( frontal )

• A panel to mount the teensy on

• Some separators for the panel

• Something for regulating power coming from eurorack to teensy?

• Something to connect the jack on the frontal for the midi type be ( the connector and the thing holding the connector to the front panel )

• -....

Teensy libraries neeed?
- https://www.pjrc.com/teensy/td_midi.html
- ...

 

[MatrixRat]

My turn to grumble, about Billboard text in posts.

Having got that outta the way, many users have started out with a pretty simple Midi controller and inspired by getting the first one working, it's usually not long before more big ideas creep in. More knobs? Buttons?

Presets? With pots? Encoders let you have multiple presets without having to twiddle everything to get stuff in sync. Then how do you know it's value? Screen perhaps?

Have not worked with Eurorack but have built an Analog synth inspired by an ancient Roland plugout CV, Trig and Gate. No plugs and sockets, just clip leads - same principle. Midi did not exist.

Looking at your project from the outside:-

TRS Midi hardware has different polarity according to which manufacturer. It's also dead easy to have a patch accident.

CV, Gate and Trig all have a same-looking socket waiting for a similar-looking plug. It's wise to add protection to TRS Midi hardware to prevent damage to either end in the event of a mis-plug.

Pots, Can have fun with noisy readings. 10K usually suggested. Higher values can be problematic. For 8 pots, 2K won't break anything, just make absolutely sure that the + end goes to +3.3v. Teensy 4x are NOT 5v tolerant.

Which Teensy? One you can get given global nonsense meaning that's most likely a T4.0 or T4.1. The high speed of the T4s can generate loads of unwanted interference especially if pins are outputting anything. Highly recommend series R on TX pin followed by a buffer before TX goes anywhere near a piece of wire - in a rack of other goodies.

Have you breadboarded anything?