Is there a way to bypass pedal calibration?

Dpoirier

Dpoirier

Fractal Fanatic
I'm using two third-party expression pedals on my III, but pedal two is not as linear as I'd like.
When I go to "setup > IO > Pedal" and press Enter to calibrate pedal 2, it's worse. The two bars that show pre- and post-calibration show exacty what seems to be wrong: the pre-cal bar moves smoothly and linearly from heel-down to toe-down, but the post-cal shows absolutely mo movement at all for the first third of the pedal's travel. In short, the results of the calibration are totally undesirable. But I can't "bypass" this calibrated (so-called) correction, other than calibrating it again (which ends up with the exact same incorrect results). When I swap my two third-party expression pedals, the problem remains on the III's pedal 2 calibration.

I don't dare calibrate pedal 1 because I don't want this screw-up on it also (I haven't calibrated it since installing 31.03).

Both my pedals work flawlessly on other equipment (including a II XL), so the calibration routine seems like a possible culprit?
If it matters, I'm on the latest 31.03 firmware.

Anyone knowledgeable out there willing to test the proper functionality of the pedal calibration?
 
Domct203 said:
Did you swap just cables to see if the problem follows?
Click to expand...
I swapped cables at pedal end, then at the back of the Axe-Fx, then swapped pedals... in all cases, it's pedal 2 that shows a calibration "curve" that entirely misses the first third of the pedal's travel.
:(
 
yek said:
That indicates the use of a wrong cable or an issue with that pedal.
Click to expand...
Well, no... It doesn't matter which of my two expression pedals I plug into the Pedal 2 jack of the axe-fx, or which TRS cable I use. The problem is the same. So in my view this does not indicate anything wrong with the pedals or the cables. The only common denominator is the Pedal 2 input and internal circuitry.
 
Pedal calibration doesn't impact the curve. It simply sets the limits of the response.

You need to verify everything in the chain.

Test your cables. Make sure tip goes to tip, ring to ring, sleeve to sleeve.

Give us details on the pedals you're using. What model? What potentiometers are in them? Open them up. Verify the potentiometers are correct and what you think they are. Verify that the potentiometer are wired correctly for use with a Fractal device. You want: wiper -tip, ground terminal - sleeve, in terminal - ring -- verify that's true for your pedal.
 
iaresee said:
Pedal calibration doesn't impact the curve. It simply sets the limits of the response.

You need to verify everything in the chain.

Test your cables. Make sure tip goes to tip, ring to ring, sleeve to sleeve.

Give us details on the pedals you're using. What model? What potentiometers are in them? Open them up. Verify the potentiometers are correct and what you think they are. Verify that the potentiometer are wired correctly for use with a Fractal device. You want: wiper -tip, ground terminal - sleeve, in terminal - ring -- verify that's true for your pedal.
Click to expand...
Why should it matter? Both of my pedals, and both of my cables, work just fine in the Pedal 1 input jack, and the whole enchilada fails when plugged into the Pedal 2 input jack! Am I missing something?
 
Dpoirier said:
Why should it matter? Both of my pedals, and both of my cables, work just fine in the Pedal 1 input jack, and the whole enchilada fails when plugged into the Pedal 2 input jack! Am I missing something?
Click to expand...
They work in pedal jack 1 after calibration?

And to confirm, you're using the process on page 12 of the manual?
 
Dpoirier said:
You see why I'm reluctant to even entertain potentiometer values and other details that seem to be irrelevant...
Click to expand...
If you're convinced it's a problem on the unit, you'll have to open a support ticket. There's nothing user-serviceable there.

Has this ever worked?
 
Just for giggles, I just used a multimeter to test the resistance range of my now infamous pedale. The resistance increases smoothly throughout the range from a low of 5 ohms to a high of about 9.5k ohms. On both of them.

Baffling!
 
I don't know if it's been asked, but based on your meter readings, it seems likely your pedals are identical (please correct me if I'm wrong). If that's the case, and you've swapped the cables and inputs in all the possible permutations, then you are probably experiencing an issue that is in the AxeFX III itself.

As noted above, the pedal calibration function only identifies the functional range limits of the controller. If you're seeing weird non-linear behavior, take a look at the curve assigned to that expression controller to ensure it's linear.

This might not be exactly the same issue, but I had a similar conundrum with my FM3 recently. After a FW update that introduced improved auto-sensing for pedals, my FM3 wouldn't respond reliably to auto-on block control with one of my expression pedals. My expression pedals on that board are both Fractal Audio EV-2 pedals, and measure exactly the same on the multimeter. I swapped the pedals, cables, and inputs. Eventually I narrowed it down to the input being used on the FM3. When I swapped the software assignment of expression 1 and 2, it worked as expected. Something in one of the expression controller inputs was acting up. Anyway, I swapped my configuration and it has been fine even since. I later read accounts that others had reported a similar problem. In a subsequent FW version, I think it may have been corrected but I haven't had a reason to switch back to test it.
 
I'm guessing that these are Boss expression pedals. Every Boss expression pedal I have ever tried, including 3 that I own, have a dead zone at the heel end extending to 25-30% of the pedal travel. It is not a problem with the Fractal calibration. Calibration on any device that you plug the pedal into can only map the change in resistance over the pedal travel. Nothing will happen on a Boss pedal until you leave the dead zone, so there is nothing to map. You would expect better from Boss, but it is what it is. It is simply poor engineering The only workaround that I have found is to insert a pad under the heel end of the pedal to limit how far it will move. You end up with less travel, but the whole of the remaining travel does something.
 
You guys are all awesome, thanks for the additional tips, I've got some things to look into when I get back home.
 
Sleestak said:
...
As noted above, the pedal calibration function only identifies the functional range limits of the controller. If you're seeing weird non-linear behavior, take a look at the curve assigned to that expression controller to ensure it's linear.
...
Click to expand...

Ding-ding, we have a winner. Sleestak, you solved it. Huge thanks!

In the setup > Pedal calibration function, it would appear that the curve of the modifier assigned to the pedal in the currently selected preset has, very surprisingly, an effect on the calibration (!!!)

I selected an empty preset (therefore no curve, no modifier, nothing assigned to the pedal) and now it calibrates properly as it should.

I'm baffled that the calibration process would even have awareness of a preset, let alone curves on modifiers, but...

Anyways, thanks, now I'm good to go (though somewhat mystified).
 
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