Using MIDI with stompboxes

[robbiemcm]

I searched online but couldn't find anything useful. If you want to use midi with a stompbox, how can it control something. Do you use it to effectively control variable resistance (not a motor driven pot though, that would be horrible for quick changes?). Or how can it control a standard effect. Or am I completely mistaken and it only works with digital effects?

[robbiemcm]

Someone must know

[eh]

midi is a digital way of control. in order to use it w. stompboxes, you´d need to program a pic with etc, like a midi - cv converter.  
you could control anything you´d like with midi, as long as you have the right hardware to do it. just requires some work as well as assembler skills.

[Paul Perry (Frostwave)]

Yeah, wiht a PIC (or other micro) you can interpret MIDI data, including controllers, and then output a proportional voltage (either by using pulse width modulation output and then filtering, or by generating a serial output to drive a digital to analog converter) and then usee the voltage to control most anything analog, eg control a LED in an optocoupler.
I have a proto of a filter here that has a LFO generated by a PIC & it syncs to MIDI as well. Plus you can sweep it via midi.
Ther eis actually quite a lot of diy midi FX stuff on the web, but I don't personally have any programming chops at all.

[Brett Sinclair]

Check out http://www.ucapps.de/

While there are no specific ready-to-build projects to control a stompbox effect, you'll find a ton of info here that might be useful (e.g. midi -> cv control).

It defenitely is something that pops up one in a while on the messageboard there. I did an experiment with AD5204 digital potentiometers and a big muff circuit, writing an assembler application based on MIOS (midi operating system  :wink: ) and the results were actually not that bad (well... it worked!).

It's a lot of work (you'll need to dig into programming) and trial and error though... the main challenge being to try and keep the noise level down as you are combining digital (the midi part) and analog circuits.

[robbiemcm]

Ok.. I only really want something really simple, like to light up an LED and then use a light sensitive resistor to act like a pot in any circuit i need, I think that would be great.

[The Tone God]

Ok.. I only really want something really simple, like to light up an LED and then use a light sensitive resistor to act like a pot in any circuit i need, I think that would be great.

I don't see why you need MIDI for this. Sounds like an optocoupler.

MIDI is a modified serial bus. You need some kind of processor to do anything with it. Do a search for MIDI. Something will come up.

Andrew