Volume pedal idea / Arduino?

andyg_prs

Hi, 

I posted this over in fx and was advised to post here for people with Arduino skills:

"Hi, 

I use a volume pedal in my effects loop.  I use it as a master volume control, not for swells or anything like that.  I've experimented with many many pedals.

I like to have fine control over my volume.  Regardless of a minimum volume control, I haven't found what I need in terms of controlling the volume performing live.  The nearest I've got is with a visual volume pedal, and modifying the tension controller on the pedal so that it's as stiff as I can make it.

However, what I envision is this:

• Two momentary switches, perhaps under a pedal that you can push so that it see-saws towards / engages one momentary switch or the other. 

• A row of LEDs like the visual volume pedal, let's say 11 LEDs for argument's sake.  The middle LED blue, the others red.

• The first blue LED is the minimum volume, the last blue LED is the maximum volume (the signal goes straight through, no boost).

That's it!

The idea is that I'd set the device where I want it....probably with the volume roughly half way.  I can tap the volume up or down.....it's only five taps to get to max or min volume from my starting point.  Maybe holding the pedal down on either momentary switch for more than a second makes the level dart to the maximum in that direction.

Anyhow, it sounds simple, but of course making a pedal that doesn't add noise / plays nicely...and has a bunch of LEDs would involve work.

Also, wondering if anyone is familiar with a switch (the up/down control) that's generally available that might suit this device?

Next is how this volume control would work....I've only worked with pots....but I guess ultimately the pot is just a rotary resistor and so each position on the 1-11 scale is just a different resistance in the path.....but of course, I have no clue how to do this.

I feel like this could take up less room on the pedalboard then your average volume pedal too.

Any ideas, feedback would be gratefully received.

And if there are any pedal builders on here who would want to quote me for creating this thing, I'd be very happy to hear from you!

If not it's research, DIY and bad soldering on my part!

Cheers,
Andy"

maharg101

How about a gigrig quartermaster flipflop with several passive volume boxes (e.g. vein-tap's leech) in the loops. Then you could select any preset volume with a single tap. It has LEDs too !

andyg_prs

maharg101 said:

How about a gigrig quartermaster flipflop with several passive volume boxes (e.g. vein-tap's leech) in the loops. Then you could select any preset volume with a single tap. It has LEDs too !

I'm sure it'd work....but far too much real-estate!....

relic245

Doesn’t really answer your question but I’m building an Ardruino based midi controller at the moment and it’s loads of fun.

Its turning out to be a way bigger project than I expected but really enjoying it.

if you enjoy creating stuff then building your own could be a good way to go for you.

relic245

Actually another thought for you. My pedal will have a vol up/down function but will be for controlling an hx fx.

what about getting something like a line 6 m5. I think tether go for peanuts these days. Then what you’re building is a simple midi controller to control a single block the m5.

andyg_prs

relic245 said:

Actually another thought for you. My pedal will have a vol up/down function but will be for controlling an hx fx.

what about getting something like a line 6 m5. I think tether go for peanuts these days. Then what you’re building is a simple midi controller to control a single block the m5.

Hi, yes, I could do that.  Ideally I wouldn't have the footprint of the M5 plus mid controller....and there's also the A/D D/A conversion (not trying to be a cork sniffer) that I'd also avoid if possible.  It could even be that the M5 could work by itself....but ultimately, mocked up, I'm looking for something like this....  Roughly 11cm wide by 6cm for example....

relic245

I get that about the footprint and conversion. 

What about something like this:
https://www.mouser.co.uk/new/analog-devices/adi-ad5204-ad5206-potentiometers/?gclid=CjwKCAjwp7eUBhBeEiwAZbHwkXi5EEDsrw2K-83YtYl4pvPJho8OsaMv7JFUErGxqOypDy7f3I0aJBoCqRcQAvD_BwE

It's a digital potentiometer. 

Maybe I'm oversimplifying it, but what you want is a volume control. A volume control in your guitar is a variable resistor, is it more complicated than using one of these and controlling it with the Arduino? That would be a fairly simple project. 

I've seen someone use these digital pots to replace the actual pots in a stompbox, basically making it midi controlled. I quite fancy trying that out as my next project. 

andyg_prs

relic245 said:

I get that about the footprint and conversion. 

What about something like this:
https://www.mouser.co.uk/new/analog-devices/adi-ad5204-ad5206-potentiometers/?gclid=CjwKCAjwp7eUBhBeEiwAZbHwkXi5EEDsrw2K-83YtYl4pvPJho8OsaMv7JFUErGxqOypDy7f3I0aJBoCqRcQAvD_BwE

It's a digital potentiometer. 

Maybe I'm oversimplifying it, but what you want is a volume control. A volume control in your guitar is a variable resistor, is it more complicated than using one of these and controlling it with the Arduino? That would be a fairly simple project. 

I've seen someone use these digital pots to replace the actual pots in a stompbox, basically making it midi controlled. I quite fancy trying that out as my next project. 

Thing is, I know my limitations.  So really, I'm looking for someone who is keen to help, happy to pay...

Petrogli

I have been on a similar path.

I built a midi contoller based on an Arduino Mega with dual expression pedals and spectacularly failed to build a viable volume device.

I got close with LDR/LED combos but they were laggy. Similar with off the shelf optocouplers.

I got near with a digital pot but the steps between the 128 discreet positions was noticable on fast sweeps such as volume swells.

I even tried controlling a real pot with a servo motor but that was also slow.

In the end, I gave up and bought a Source Audio programmable EQ. https://www.sourceaudio.net/programmable-eq.html

It is a midi controllable eq but the master volume of the device can also be managed using midi.

I'm not sure if that fits your use case but it has solved about 10 years of my headaches trying to concoct something.

Cheers,

Neil

andyg_prs

Petrogli said:

I have been on a similar path.

I built a midi contoller based on an Arduino Mega with dual expression pedals and spectacularly failed to build a viable volume device.

I got close with LDR/LED combos but they were laggy. Similar with off the shelf optocouplers.

I got near with a digital pot but the steps between the 128 discreet positions was noticable on fast sweeps such as volume swells.

I even tried controlling a real pot with a servo motor but that was also slow.

In the end, I gave up and bought a Source Audio programmable EQ. https://www.sourceaudio.net/programmable-eq.html

It is a midi controllable eq but the master volume of the device can also be managed using midi.

I'm not sure if that fits your use case but it has solved about 10 years of my headaches trying to concoct something.

Cheers,

Neil

Interesting to hear.....I reached out on FB and a friend who plays keys turns out to have an electronics degree, runs a tech business and is keen to see if he can help.  I'm going to see him on Monday.  In my case I don't use the volume pedal for sweeps, but either way, I'm keen to see what he thinks.  I'll keep everyone informed!

urban_winter

Digital pot and arduino would be really easy for this usage, I think. I reckon you could get it going on a breadboard in an afternoon.

[Quick google]

Less than an afternoon, actually: https://www.arduino.cc/en/Tutorial/LibraryExamples/DigitalPotentiometer

U.

Stratavarious

I do a lot with arduino for midi and triggering stuff but agree that a programmable EQ with patches and a midi controller could be the winner.. BOSS EQ200 maybe or a multifx with volume adjusted patches in sequence.

I use the switchable EQ control on my mesa boogie as both shaping and an extra level boost if I set the sliders +ve