HELP - Axe-Fx Suddenly Not Reacting To Expression Pedal's Full Sweep

shredi knight

Power User
Last night I was trying to diagnose some zipper noise I was having with one of my 2 expression pedals (Boss FV-500H). With the patch I was using, expression pedal #1, which is directly plugged into my Ground Control Pro midi floor board's pedal jack, is attached to a Drive block and controls the amount of gain. Expression pedal #2 is directly plugged into the pedal jack on the back of the Axe-Fx and is attached to a Delay block and controls the level of the delay (no delay with the pedal all the way down/full delay with the pedal fully raised that is equal in volume to the dry signal ). Expression pedal #1 is the one that I was having the zipper noise issue with.

I wanted to see if the zipper noise was an issue with the pedal itself, or something else, so I switched how they were connected to test if the noise would still happen with the other pedal. I unplugged the TRS cable (the one connected to the Ground Control Pro) from expression pedal #1 and plugged it into expression pedal #2. After testing (I can't even remember now if there was still zipper noise:rolleyes:), I reconnected the pedals how they were originally, and that's when my real problem started.

I started playing on the same patch and immediately noticed that the delay was very loud even though the pedal controlling it was all the way down (expression pedal #2, the one plugged into the Axe-Fx's pedal jack). I took a look at the Delay block's Modifier page and saw this on the display graph:

SAM_0282_zpsz0mdf7bq.jpg




With the pedal all the way down, the black ball on the graph should be all the way in the bottom right corner. When I sweep the pedal through it's range, it goes from where you see it in the picture, to the top left corner, which is only about a third of the available range.

My first thought was something must be wrong with the pedal, but when I hooked up my other pedal (#1) to the Axe's pedal jack, it behaved the exactly the same way. I also tried using different cables, but it made no difference. When I tried plugging pedal #2 into my Ground Control Pro and not the Axe-Fx, it controlled the Delay normally, with full range. That can only mean the problem is with the Axe-Fx, it's the only constant.

After that I tried recalibrating the pedal several times (Axe's I/O menu, "Pedal" page), and even reinstalled the latest firmware, but nothing changed. The only thing I haven't tried that I can think of if a system reset, but I really don't want to have to re-setup everything again when I doubt that's going to solve the problem.


So that's where I'm at. I switched the way I had my pedals hooked up, switched them back, and for some reason that made my Axe-Fx stop working correctly with them. Anybody ever have anything like this happen to them or have any ideas what the problem is?

Thanks.



P.S. Sorry for the long ass description, I have a bad habit of over explaining things.:D


EDIT - Here's something I just noticed:

SAM_0283_zpsgscghiqc.jpg



This is what the Modifier page looks like when my pedal is fully raised (I have the sweep reversed in case anyone is wondering). I have to move the pedal about halfway through its range before that black dot even starts to move now. Its like it's way up in that corner. That sort of explains why it doesn't reach the bottom corner when my pedal if pressed fully down.
 
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what model is the pedal? is the TRS cable plugged in all the way? is there any "Min value" knob on the pedal itself? any switches for polarity you may have turned?
 
what model is the pedal? is the TRS cable plugged in all the way? is there any "Min value" knob on the pedal itself? any switches for polarity you may have turned?


I give the model in my op (Boss FV-500H), unless you are referring for something else. Cables plugged in all the way. There is a min value knob on the pedals, but they are in the same positions they have always been and weren't moved before this happened. Turning them now doesn't help any. No switches.

One thing I just noticed:

SAM_0283_zpsgscghiqc.jpg



This is what the Modifier page looks like when my pedal is fully raised (I have the sweep reversed in case anyone is wondering). I have to move the pedal about halfway through its range before that black dot even starts to move now. Its like it's way up in that corner. That sort of explains why it doesn't reach the bottom corner when my pedal if pressed fully down.

I'll add this to my op.
 
I give the model in my op (Boss FV-500H), unless you are referring for something else. Cables plugged in all the way. There is a min value knob on the pedals, but they are in the same positions they have always been and weren't moved before this happened. Turning them now doesn't help any. No switches.

One thing I just noticed:

SAM_0283_zpsgscghiqc.jpg



This is what the Modifier page looks like when my pedal is fully raised (I have the sweep reversed in case anyone is wondering). I have to move the pedal about halfway through its range before that black dot even starts to move now. Its like it's way up in that corner. That sort of explains why it doesn't reach the bottom corner when my pedal if pressed fully down.

I'll add this to my op.
Yeah I missed the model numbers.

Make sure the Min value knob is fully counter clockwise.
 
-Does it do it on all patches?

-Does it do it if you set it up as something else like a wah?

-Did you try deleting that delay block in that patch and just redoing the delay block & modifier?

-And this was the pedal that was NOT the one you originally thought was the culprit of the zipper noise correct?

-Can you recalibrate thru the Ground Control instead of direct to the back of the AxeFX?
 
-Does it do it on all patches?

-Does it do it if you set it up as something else like a wah?

-Did you try deleting that delay block in that patch and just redoing the delay block & modifier?

-And this was the pedal that was NOT the one you originally thought was the culprit of the zipper noise correct?

-Can you recalibrate thru the Ground Control instead of direct to the back of the AxeFX?


- Yes.

- Yes, it does it with all the blocks.

- Yes.

- Yes, but it behaves the same way with both pedals, and with different cables.

- The Ground Control Pro actually has 2 pedal jacks. The reason I don't use both is because of a known flaw in the unit where one pedal doesn't calibrate correctly if you have 2 plugged in at the same time. Like on the Modifier pics I posted above, the second pedal will only go from say like 0-95 instead of 100, or something like that (it's been a long time since I've tried it). I ran into that problem when I first got the GCP, then found out about it being a known problem with the unit from a fellow user on a forum (possibly this one). So I always just ran the second pedal through the Axe-Fx. I suppose I could compensate using the second pedal through the GCP by altering the scale in the Axe-Fx's Modifier page (I probably didn't know to try that back then). If I can't get this problem with the Axe-Fx figured out, I guess I'm going to have to try that.
 
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i think the issue is the on-board Pedal jack, not the GCP. so we can remove that from the equation.

at this point, the only things that can cause the issue are

the TRS cable or connection point
calibration in the Pedal menu
the Min Value knob on the FV500
the physical jack on the FV500
the pedal/pot in the FV500
the physical jack on the Axe-Fx Pedal port

i know many of those were adjusted, but i think those really are the only possible causes.

i'd first try yet another TRS cable, maybe put it in and out of the expression jack several times briskly - maybe a prong is stuck or something.

the Axe isn't getting the correct information and it seems like it's not anything to do with the FV500 itself since you tried 2. i doubt it's something in the firmware. so i'd definitely try another different TRS cable. hard to tell from just text.

if there's any way you could do a video showing the actual components, plugging them in, etc. it might help.
 
Are you plugged into the expression outs of the Boss pedals?


Yes. The pedals wouldn't work at all otherwise.




i think the issue is the on-board Pedal jack, not the GCP. so we can remove that from the equation.

at this point, the only things that can cause the issue are

the TRS cable or connection point
calibration in the Pedal menu
the Min Value knob on the FV500
the physical jack on the FV500
the pedal/pot in the FV500
the physical jack on the Axe-Fx Pedal port

i know many of those were adjusted, but i think those really are the only possible causes.

i'd first try yet another TRS cable, maybe put it in and out of the expression jack several times briskly - maybe a prong is stuck or something.

the Axe isn't getting the correct information and it seems like it's not anything to do with the FV500 itself since you tried 2. i doubt it's something in the firmware. so i'd definitely try another different TRS cable. hard to tell from just text.

if there's any way you could do a video showing the actual components, plugging them in, etc. it might help.


You really need to see a video of me plugging a TRS cable in & out of the Axe-Fx? That sounds like some kind of weird techie fetish porn :p (sorry, couldn't resist that).

I really don't think it's the pedal jack on the Axe-Fx. I never unplugged the TRS cable from it until after this problem arose (I see that I worded that wrong in my op). All I did was unplug the TRS cable from one pedal and plugged it into the other. In fact, now that I think about it, I believe I unplugged the cable from pedal #1 (that's connected to the GCP) and plugged it into pedal #2. So I never actually had a different pedal connected to the Axe-fx. I had a different pedal going to the GCP. (yeah, I really worded that wrong in the op :rolleyes:) When I plugged the TRS cable that was connected to the Axe-fx back into pedal #2, the Axe acted like it didn't recognize it.

I really hope that makes sense. :D

(Edit - I fixed my op so it's now worded correctly on how I changed the connections to the pedals.)



I'll dig around and see if I have some more TRS cables to try (I have an old duffle bag that's packed with various cables and guitar odds & ends that I accumulated over the years). I'll also try clean the insides of all the various jacks with contact cleaner and a Q-Tip.


Does anyone think it is worth a shot to try doing a system reset on the Axe-Fx?
 
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Does anyone think it is worth a shot to try doing a system reset on the Axe-Fx?
i really don't think so.

as mr_fender asked, you're using the Expression port on the FV500, right? i know these questions sound remedial, but we can't see what you're doing so we have to ask. and yes, i've solved problems before with videos like that :) typically people with an issue tell things they think are important and leave out other details.

the other day someone asked why their pedal didn't work on an AX8. i asked for some pictures. they showed the screens, different menus, etc. but i noticed that on the top edge of one pic, i could just barely see the cables. the cable for the Pedal plug was way too far right. i asked what port his pedal was plugged into.

turns out it was in Output 1. but i'd never know that until i saw the pic. so easy to assume certain things - on both sides! pics and videos just help. always. and presets of course. it just helps rule things out.
 
Since it's a sudden change after moving cables around, it's likely a bad connection or bad cable. Do both pedals give the same behavior when plugged into the Axe and recalibrated? If so, I'd try a different cable.

As for the zipper noise, did you by chance have dampening turned all the way down for the attached modifier?
 
i really don't think so.

as mr_fender asked, you're using the Expression port on the FV500, right? i know these questions sound remedial, but we can't see what you're doing so we have to ask. and yes, i've solved problems before with videos like that :) typically people with an issue tell things they think are important and leave out other details.

the other day someone asked why their pedal didn't work on an AX8. i asked for some pictures. they showed the screens, different menus, etc. but i noticed that on the top edge of one pic, i could just barely see the cables. the cable for the Pedal plug was way too far right. i asked what port his pedal was plugged into.

turns out it was in Output 1. but i'd never know that until i saw the pic. so easy to assume certain things - on both sides! pics and videos just help. always. and presets of course. it just helps rule things out.


I really appreciate the help, so thank you (and everyone else who has posted), but It would really be a pain to make, upload, and post a video. I can post pictures though.


I can assure you my TRS cable is plugged into the expression port on the pedal (I double checked it just today). I've had this same set-up for at least 4 or 5 years and know exactly how everything is connected, which is the same as how is always been connected.


I really don't see what I could be leaving out. it's really as simple as I've said:


- I unplugged one TRS cable from the expression pedal (the cable that connects to the Axe-Fx's pedal jack).

- I plugged another TRS cable into that pedal (the cable that connects to the GCP pedal jack).

- I played with the pedal for a few minutes.

- I plug the TRS cable that is connected to the Axe-Fx back into the pedal.

- The pedal no longer works correctly with the Axe-Fx.


That's all that happened. I know it doesn't make any sense why the Axe-Fx is behaving the way it is, but it is. It's like the GPC corrupted the pedal.


I'm going to mess with it and try a couple of things and see if I can get it working right again. If it does turn out to be something simple that I am overlooking, I'll have no problem admitting it and you can all call me an idiot. :D


Thanks again.
 
In all the posts above, I don't see anywhere where you said that you tried a different pedal directly into the Axe.
In fact, now that I think about it, I believe I unplugged the cable from pedal #1 (that's connected to the GCP) and plugged it into pedal #2. So I never actually had a different pedal connected to the Axe-fx.

Let's give that a go, and see what happens.
 
I respectfully beg to differ:
:)

But then, 11 posts later, you said:


In fact, now that I think about it, I believe I unplugged the cable from pedal #1 (that's connected to the GCP) and plugged it into pedal #2. So I never actually had a different pedal connected to the Axe-fx. I had a different pedal going to the GCP.
Which makes it sound like you didn't do that.
 
But then, 11 posts later, you said:



Which makes it sound like you didn't do that.


I did it after I realized something wasn't right.

What might be confusing you is that I edited my original post where I initially said I hooked up my other pedal to the Axe-Fx, and when I switched it back to the way it was, the problem showed up. That's what I was referring to in the post you quoted. I realized that wasn't how it happened. I actually hooked a my other pedal to my GCP.

After
that is when I tried the other pedal through the Axe.
 
Understood. So what was the result of that test? Does the problem follow the pedal, or...?
 
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