How to run an expression pedal to multiple other pedals?

August 20, 2018 8:01 PM

Guitar players—what is the best way to run a single expression pedal through 3-4 other pedals simultaneously?

I never owned an expression pedal until recently (Moog EP-3), but as I'm buying more pedals and recording a lot, I realize I don't want to keep switching the cable between pedals — I want the exp pedal to output to 3-4 pedals at a time, ideally...

So should I:

1. Sell the Moog and get one of the Mission Engineering pedals that has 3 outputs
2. Get an Expressionator box
3. Get a splitter cable (but would that compromise the signal?)


Another product I've become familiar with since digging into this is the CoPilot Broadband which would seem to do everything I want...but I can't seem to find very many mentions of the company or the pedal online which makes me hesitant.

Any advice would be great!

posted by deern the headlice to Media & Arts (6 answers total)

Response by poster: Or for that matter, would one of these little splitter boxes work, instead of shelling out for something like the Expressionator?
posted by deern the headlice at 8:03 PM on August 20, 2018

It would be difficult to say if this could be done with any specifics, especially if the pedals are different brands. There's no telling what they each want to "see" come out of an expression pedal patch cord. I suspect they want a variable resistance of one kind or another. But what value? And it's certainly possible they I imagine the might want a control voltage instead. If they all want a CV input, that would be easy. But that would be more likely with Moog equipment. For the rest of the world, as far as I know, there's no standard for expression pedal interface.
posted by 2N2222 at 9:22 PM on August 20, 2018 [1 favorite]

This might be a good question to ask on the Wampler Tone Group on Facebook- it's the best community of knowledgeable and polite electric guitarists I've found thus far.
posted by EKStickland at 12:12 AM on August 21, 2018 [1 favorite]

i know about electronics but not guitar pedals. this page seems to summarize the situation pretty well. If your pedals are the potentiometer type then there can only be one fx pedal passing its input voltage thru the potentiometer at a time. In this case youd need a pedal with many potentiometers attached to one shaft. an electronics inclined friend might be able to build / mod such a device.
posted by scose at 2:32 AM on August 21, 2018 [1 favorite]

They are in bypass mode if they aren't turned on, or occasionally bypass status on the multi-effects is identified by a blinking light.
posted by The_Vegetables at 8:40 AM on August 21, 2018

Best answer: The Moog pedal sends CV, which is a DC voltage. The pedal is probably something like up=0v, down=5v or something like that (possibly reversed, or reverse-able, or scalable from 0-5v up to 0-10v).

If you want all your pedals to respond to exactly the same voltage swing, a splitter (aka Multiple) will do that - send the same DC voltage to each pedal. A passive (unpowered) splitter/multiple will indeed send the same voltage to multiple pedals at once, but there could be a (tiny, probably unnoticeable) voltage drop. An active (powered) splitter or multiple will replicate the expression pedal's cv output exactly. But an audio splitter like you linked to is not designed to split DC voltages, in fact it's most likely designed to remove "DC offset" from any audio signal (which is in essence an AC signal) so it probably won't respond to your expression pedal output as you'd expect. You'd want a specific CV splitter or multiple. These certainly exist in studio rack gear and modular synth gear, but I don't know if you'll find one specifically for guitar pedals.

But you probably don't want to send the same exact voltage to each pedal simultaneously, because you're presumably controlling different parameters on each pedal - depth, speed, etc. and there would be no reason to control them all the same: at the same time with the same voltage - in fact that sounds limiting. Therefore, the Expressionator box you link to sounds ideal for what I think you are wanting to do - use one CV expression pedal to send different cvs to different guitar pedals at the same time.

Gah I hope that all makes sense.
posted by gyusan at 10:04 AM on August 21, 2018 [2 favorites]