Mission Expression Pedals with an FC

MKeditor

MKeditor

Experienced
I've been using my EP-1 & SP1-LP Mission Expression pedals for many years. They've worked great with the Liquid Foot, MFC and the RJM MMGT. With the FC it's almost full volume when the pedal is only 50% down. I've recalibrated twice. Changing the tapper has not much affect. Of course I can change the middle parameter in the modifier but I'd have to do that for every preset. Then I have change all again to use the RJM. IS there a better way?1000023874.jpg
 
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MKeditor said:
I've been using Mission Expression pedals for many years. They've worked great with the MFC and the RJM MMGT. With the FC it's almost full volume when the pedal is only 50% down. I've recalibrated twice. Changing the tapper has not much affect. Of course I can change the middle parameter in the modifier but I'd have to do that for every preset. Then I have change all again to use the RJM. IS there a better way?
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When you calibrate, try moving the pedal slowly and confirm it's a smooth movement across the range.

Also, make sure you're calibrating the FC ports and not the Axe Fx ports. The calibration is in different places for each.

Finally, make sure you press the Enter button on the front panel after calibration as mentioned on the screen.

See page 8 here:

https://www.fractalaudio.com/downloads/manuals/FC-X/FC6+12-Owners-Manual.pdf

Which Tapers did you try? Linear might work better for you although analog volume pedals are normally Log as far as I'm aware.

Hope that helps...
 
I believe RJM products use a different polarity for their expression pedals (Ring to Wiper I think). Fractal products use the Boss/Roland polarity (Tip to Wiper). Which model of Mission pedal do you have?
 
mr_fender said:
I believe RJM products use a different polarity for their expression pedals (Ring to Wiper I think). Fractal products use the Boss/Roland polarity (Tip to Wiper). Which model of Mission pedal do you have?
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EP-1 & SP1-LP. I originally bought them in 2009 to use with a Liquid-Foot controller. Then an MFC and finally an RJM.
 
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mr_fender said:
I believe RJM products use a different polarity for their expression pedals (Ring to Wiper I think). Fractal products use the Boss/Roland polarity (Tip to Wiper). Which model of Mission pedal do you have?
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What's a wiper? Does the info above clarify? If wiper = sleeve, the way I read it, the FC should be the same as the RJM. Unfortunately, the FC manual sheds no light on which configuration Fractal uses.
 
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The wiper is the variable ohm contact of the potentiometer. Fractal uses the Boss/Roland polarity of Tip to Wiper which is what Mission uses on their standard expression pedals. RJM uses the Korg/Yamaha polarity of Ring to Wiper. The EP-1 (if stock) should work fine with Fractal gear, but has the wrong polarity for the RJM. I can't find any info on an SP1-LP model so I'm not sure of the polarity on that one.

Make sure you are using standard TRS to TRS cables with both pedals and calibrating in the FC Controllers menu and NOT in the I/O menu of the Axe III.
 
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I found that if I switched the tapper to 5A it's workable. But I'm having to tweak all the levels of the time based effects that the other pedal controls. It works but will be a pain if I switch from the RJM to the FC and vice versa. Thanks for the input.
 
You shouldn't need to change the taper at all if the pedal is correctly calibrated. If you have a multi-meter, verify your cables are straight through TRS cables (tip to tip, ring to ring, and sleeve to sleeve). You can also verify the pot wiring, value, and taper as well. If the pedal and cable are wired correctly, the resistance between the tip and sleeve should go down while the resistance between the tip and ring should go up as you move the pedal and vice versa. The resistance between Tip and Sleeve should read roughly close to zero ohms at heel down, roughly close to 10k ohms at toe down, and about half that with the pedal half way through its travel.
 
mr_fender said:
If the pedal and cable are wired correctly, the resistance between the tip and sleeve should go down while the resistance between the tip and ring should go up as you move the pedal toward heel-down and vice versa.
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FIFY. :)

[edited for correctness]
 
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Actually that's backwards. Tip to Sleeve has the highest value at toe down. The wiper will have the highest resistance to ground for maximum output from the voltage divider, so it should read close to the total value of the pot.
 
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