# Leprechaun with Expression Pedal ?



## Dali (Nov 16, 2019)

Hello builders,

The building docs mentions on page 4 "Wiring diagram with expression input jack".

Anyone here made that build? Is it worth it?

There is no information about the kind of Expression pedal compatible or that you need to build to make it work.

Any information is appreciated!


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## DGWVI (Nov 16, 2019)

The Moog Ep-2 and Ep-3 will work, according to the Rainbow Machine webpage


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## phi1 (Nov 16, 2019)

Pretty much any expression pedal with TRS connection should work, I believe. The exp pedal controls an fv-1 parameter (pitch). The pot of the exp pedal creates a voltage divider which sends a voltage to the fv-1. So the fv-1 doesn’t care what the total resistance value of the exp pedal is because any value will still make the voltage divider.


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## p_wats (Nov 18, 2019)

I added the expression input on mine and find it useful for weird pitch sweeps, etc.


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## Dali (Jan 5, 2020)

Would "made for keyboards" expression pedal works as long as they are TRS?

Something like:

https://www.amazon.com/M-Audio-EX-P-Expression-Pedal/dp/B000NLRWEI 

It says in the description: "... and effect devices with an expression pedal input".


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## p_wats (Jan 5, 2020)

Dali said:


> Would "made for keyboards" expression pedal works as long as they are TRS?
> 
> Something like:
> 
> ...



I've used several different expression pedals with mine and it didn't seem too picky. There's a cheap m-audio one that has a switch on the bottom for the two main wiring options too.


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## chongmagic (Jan 6, 2020)

DGWVI said:


> The Moog Ep-2 and Ep-3 will work, according to the Rainbow Machine webpage



I can confirm that the EP-3 works, it worked fine with my build.


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