CV Inputs -- can I use a pot + Shruthi's own 5V source?

This could be a really dumb idea, because I likely don’t understand it at all, but…

Shruthi has CV Input pins that are basically unused in a stock Shruthi build. Through the Modulation menu, I can apparently map this CV to all kinds of things such as Filter Cutoff (e.g. CV1>cutoff). Also it seems like the CV here is 0 to +5V.

So it got me thinking, could I tap into Shruthi’s onboard +5V pin, route it through a pot (not sure what value R), and then send it back into one of the CV Inputs? That way I could use the pot to scale from 0 to +5V?

Then if I changed the modulation destination to Filter Cutoff, then basically what this gives me is a dedicated pot to adjust the Cutoff (as long as I set the Modulation menu correctly)?

I’m imagining that it would be cool to use these CV inputs to make dedicated pots for cutoff, resonance, lfo…

Also, another question: When using different filters, the modulation menu is always the same. e.g. if I have a SP filter type, why is there no mod destination for Filter Feedback? Was this just not added because nobody asked for it, or is there some technical limitation?

Nobody has used pots with the 5V into the CV INs? If this is a good idea that will work, what type of pot would be best? B10K? I cannot find any info on the forum because all the old threads link to info that no longer exists (or I cannot find), such as a “Shruthi FAQ” and most of the talk of using the CV is as input jacks, not pots. I really want to try this but I don’t want to fry my Shruthi in the process…

Yes, you can use the input pins the way you describe. There are 5v and ground pins right next to the CV input pins to make it easy to do it. I put a little PS2-style joystick on mine, although it’s a little cumbersome to use it as a pitch bend - it’s tricky to fine-tune the oscillator pitch to match the offset of the joystick at a neutral position, but more importantly (especially for your intention to use a dedicated filter cutoff pot) it only checks the inputs at a rate somewhere around 10-20 hz. This means that it’s not as responsive as using the built-in pots, there’s audible stepping as the values change, and if you’re looking to do acid-style knob tweaking it might not work. You can make it smoother if you use a lag operator instead of the CV directly, but it still might not be as fast as you want.

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