GCP with GCX, AxeFx and Ernie Ball volume pedals

[DF400]

Hi,
I am using a GCP with a GCX, then into the AxeFx and on to a GR33. I go midi from the GCP -> GCX -> AxeFx, with the volume pedals (VPJR 6181 25k) hooked up to the GCP. The issue I am having is that when I try to go through the GCX, and activate any IA, I get the "Active" light - which stay lit from that point on. Then I have no response from the pedals.

Also, when setting up the pedal assignment on my various presets, I am not able to see any movement of the numbers indicating the sweep. I tried swapping the cables (input and output).

One last question: I have read the various comments on use of expression pedals and understand that nearly all passive pedals work. However, I am getting a non-linear response (only the lower 50 % of the pedal responds). I am sure that this has been posted, so if someone would be so kind as to point me to the correct post. I can't seem to find the solution.

Thanks,

[JohnClark]

Hi,
I am using a GCP with a GCX, then into the AxeFx and on to a GR33. I go midi from the GCP -> GCX -> AxeFx, with the volume pedals (VPJR 6181 25k) hooked up to the GCP. The issue I am having is that when I try to go through the GCX, and activate any IA, I get the "Active" light - which stay lit from that point on. Then I have no response from the pedals.

When the GCX is enabled within the Ground Control Pro, the Active LED should remain lit up on the GCX whenever the Ground Control Pro is connected to the Pedal In jack (well that is after the startup splash screen sequence has finished on the Ground Control Pro).
As for the Instant Access buttons not doing what you want... what do you have them programmed to do? You can check this in the Instant Access section under Setup Mode.

Also, when setting up the pedal assignment on my various presets, I am not able to see any movement of the numbers indicating the sweep. I tried swapping the cables (input and output).

One last question: I have read the various comments on use of expression pedals and understand that nearly all passive pedals work. However, I am getting a non-linear response (only the lower 50 % of the pedal responds). I am sure that this has been posted, so if someone would be so kind as to point me to the correct post. I can't seem to find the solution.

Thanks,

I am unsure how both these conditions can exist... if you see no number sweep within the Ground Control Pro preset when looking at the settings for the Expression Pedal ports, then that means that the Ground Control Pro is sending no MIDI information when you sweep the pedals. If no MIDI information is sent then there should be no response at all from your MIDI devices.
Try connecting only one of your expression pedals and check for the position numbers displayed within a Ground Control Pro preset to sweep from 0-127. Let me know what you find.

[MJX]

One last question: I have read the various comments on use of expression pedals and understand that nearly all passive pedals work. However, I am getting a non-linear response (only the lower 50 % of the pedal responds). I am sure that this has been posted, so if someone would be so kind as to point me to the correct post. I can't seem to find the solution.

Thanks,

I am unsure how both these conditions can exist... if you see no number sweep within the Ground Control Pro preset when looking at the settings for the Expression Pedal ports, then that means that the Ground Control Pro is sending no MIDI information when you sweep the pedals. If no MIDI information is sent then there should be no response at all from your MIDI devices.
Try connecting only one of your expression pedals and check for the position numbers displayed within a Ground Control Pro preset to sweep from 0-127. Let me know what you find.

Hi John,

Sorry for resurrecting a ten year old thread, but this was the most relevant one I could find. I am experiencing a similar issue as DF400 noted regarding non-linear response. I am using an Ernie Ball VPJR 25K (for active signals) as an expression pedal thru the GroundControl Pro to control the TC Gmajor2's output volume. The pedal activity successfully converts to MIDI data and successfully controls the Gmajor's output volume...but the volume doesn't audibly change until I have already pressed halfway thru the pedal's range of motion. It's not very smooth and seems not right.

My question is: when using a volume pedal as a GCX expression pedal: should I be using a 250K passive pedal rather than a 25K active pedal? I can't tell from DF's OP, but it seems like they were using a passive pedal, yet were having the same issue(?). So does the 25K/250K problem not apply here and its something else?

Thanks

[SlapHand]

I’m not John...

Just want to share my findings after having the same issue.

The EB Volume pedals have a logarithmic response curve. They push CC# at a higher rate the closer you get to the toe position.

I have tried 3 different EB Volume pedals to control my G Major 2 via the GCP and they all act the same.

As I understand it from reading up on the topic, we need a pedal that use a linear pot to get an even response from heel to toe.

Feel free to correct me if I’m wrong because I’m about to order an Mission Engineering EP-1-BK SPL.

[MJX]

I’m not John...

Just want to share my findings after having the same issue.

The EB Volume pedals have a logarithmic response curve. They push CC# at a higher rate the closer you get to the toe position.

I have tried 3 different EB Volume pedals to control my G Major 2 via the GCP and they all act the same.

As I understand it from reading up on the topic, we need a pedal that use a linear pot to get an even response from heel to toe.

Feel free to correct me if I’m wrong because I’m about to order an Mission Engineering EP-1-BK SPL.

Interesting. That sounds like it would make sense, at least in theory. Two questions:

• When you say you tried 3 different EB VP's, did you try both 25K and 250K (active vs. passive)?
  Is the Mission EP1BK SPL the only linear range pedal you found? Any other options in your research?

That is helpful info, tho. Thanks.

[SlapHand]

All EB volume pedals I tried are passive.

I ended up buying a Mission Enginering EP25K and it works very well. The Mission Engineering EP-1-BK SPL I mentioned in my previous post is spring loaded and go back to heel position whenever you take your foot off. Not very smart if you want to control volume or set delay time etc. with it.

Anyhow... Getting a pedal with linear pot solved the problem. I did not research much as I know Mission E. pedals from another rig of mine and went for the brand I know and is satisfied with.

Without being certain, I guess any expression pedal with linear pot and TRS cable would do the trick.

---SlapHand---

[Marlboro05]

Hi there,
I have an MXR High again Volume pedal that I gutted and put a stereo jack in and soldered wires directly from the pot to the jack, works better than before I did it.