DIY Wah/Vol Expression Pedal

Morbid

Morbid

Inspired
Greetings Fractalites.
I happen to be a tinkerer...always have been. Recently I decided I wanted to make my own switchable expression pedal for a wah, by using a broken Dunlop Wah pedal, to be used with my Axe-FX II and MFC101.

I decided I would follow this tutorial to do it: http://dsguitarengineering.com/blog...de-1-build-an-indestructible-expression-pedal

I've got the pedal, I've got the TRS jacks, I'm just waiting on the 1k resistors to arrive from china (I'm patient...lol)and I can get started. But while waiting, I started thinking about how before I got an MFC, I was using a Pod HD500 to control the Axe-FX. It was better than nothing, but the only thing I really enjoyed about it ,was the expression pedal, and the ability to use it as a Volume Pedal, and then press hard to turn it into a wah pedal.

I'd like to be able to do that with the Expression Pedal I want to make, in an effort to save some footprint, but I'm not really sure where to start.
Anyone got an ideas on how i can make this happen?
 
if you want to keep it low tech you could use the toe switch to switch the out put to a second trs jack, this would be like having two pedals, but you could only use 1 at a time just like the pod setup.
 
Now that I think about it, I may try this with one of my sp-1 missions. Then I would not have to use volume blocks, or mixer blocks to switch the expression. this will save some space on the grid and on the floor when I get an AX-8.
 
paranoid said:
Now that I think about it, I may try this with one of my sp-1 missions. Then I would not have to use volume blocks, or mixer blocks to switch the expression. this will save some space on the grid and on the floor when I get an AX-8.
Click to expand...
If you give that a shot, let me know how you go about it. While I may enjoy tinkering, I'm really not sure where to start with that idea in terms of how to wire it, haha.
 
I am not sure of the wiring with out opening one up, but I would assume you would share the ground and only need to switch the tip or the ring. I would have to draw a chart on how the sp switch functions. I have opened 1 up to clean it and there are many polls on the sp-1 switch and I am not sure if it is latching or momentary. You would have to use a latching double poll switch. possibly double poll double throw.
 
if you have access to an ohm, or continuity meter you could see if the switch makes contact with 2 of the three and then switches from one of those to the other, if so the switch may work. if not a switch probably would not be that expensive.
 
Had a lot of cool stuff there last year. a lot of venders from all over the place. lot of vintage stuff. I am going to try to make it on Saturday.
 
The problem you'll ran into is that the potmeter needs to be a 10k-100K lineair taper to control the Fractal.
Lineair potmeters are not good for volume. Since our ears listen logarithmic, the volume pot needs to be logarithmic taper (also called audio taper) too.
What happens if you use a lineair potmeter as a volumecontrol is that it will be on/off more or less.

On a side note, I'm busy with a Vox pedal for exactly the same idea. Good to have some gear getting a 2nd life!
And even I use a double pot (with two tapers). 1 for expression and one for volume.
The volume will be lineair, but it's ment to be a on/off on purpose, so for me it's good.
I will use it only to handle an audio player, so I can throw audio sounds in my songs.

But to be short, control your volume with a block in the Axe.
 
GibsonLesPaul said:
But to be short, control your volume with a block in the Axe.
Click to expand...
I might be misunderstanding, and please forgive me if I am, but that's how I had it set up with the HD500 when I was using it as a controller.
I had a Wah block, and a Vol block. The Vol block was always on, and the Wah block would only enable when I'd press the toe down hard. At that point, the volume wouldn't change, but the pedal would then operate the wah.

Basically, I'd be wanting to use the pedal purely as an expression pedal, operating everything through the Axe, but I'd like to be able to switch from Vol to Wah block with the one pedal.
 
Ah, with the switch you want to tell the Axe, use the expression pedal for Wah or Volume.
While the pedal still is 1 expression pedal.
When you use a latching switch and connect that one to the switch input on the Axe it is possible.
 
GibsonLesPaul said:
Ah, with the switch you want to tell the Axe, use the expression pedal for Wah or Volume.
While the pedal still is 1 expression pedal.
When you use a latching switch and connect that one to the switch input on the Axe it is possible.
Click to expand...
Then perhaps the way the pedal in the aforementioned tutorial is wired will work the way I want.
 
Yes Morbid the pedal will work that way, and the switch will more then likely also work as an external switch connected to the mfc. What I am thinking about is a switch that will ab the expression pedal internally so there is no need to use internal blocks in the axe to mute the volume/wah to change its function..
 
not a waste, got me interested in if I can modify my sp-1 missions to save internal block usage in the soon to purchase( when I get my invite) AX-8
 
Ok, so I am not totally understanding how this works, but I am very interested in setting up an expression pedal in this sane fashion. I just got a great deal on an ep-1 which I wanted to mod to add a toe switch and I wanted to have it function exactly like this. Volume, hard press toe turns it to wah, second hard press toe back to volume. I will be connecting directly to the axe, no mfc. But I don't totally under stand how you guys are saying this would work?
 
Pwrmac7600 said:
Ok, so I am not totally understanding how this works, but I am very interested in setting up an expression pedal in this sane fashion. I just got a great deal on an ep-1 which I wanted to mod to add a toe switch and I wanted to have it function exactly like this. Volume, hard press toe turns it to wah, second hard press toe back to volume. I will be connecting directly to the axe, no mfc. But I don't totally under stand how you guys are saying this would work?
Click to expand...
Don't think you'd be able to do it without an MFC. To my knowledge, you need to have 2 Expression Inputs. One for the switch, and one for the pedal itself.
 
Pwrmac7600 said:
Ok, so I am not totally understanding how this works, but I am very interested in setting up an expression pedal in this sane fashion. I just got a great deal on an ep-1 which I wanted to mod to add a toe switch and I wanted to have it function exactly like this. Volume, hard press toe turns it to wah, second hard press toe back to volume. I will be connecting directly to the axe, no mfc. But I don't totally under stand how you guys are saying this would work?
Click to expand...
It may not work but I am thinking, an a/b switch in the expression pedal so that it switches the variable pot from 1 trs jack to another. with just a toe switch it is still a single expression but you have a remote switch, you have to set your patch up with blocks to mute un mute the effect you are controlling. either way As morbid posted you will need 2 pedal jacks. if you have an ultra or an xl,xl+ you can do this plugged in the back panel.
 
You must log in or register to reply here.
Back
Top Bottom