GCX buffer and reverse wah issue

Q & A for building and interfacing your rack gear with Ground Control Pro and GCX-based systems.
Post Reply
bettsaj
Posts: 234
Joined: Fri Jun 11, 2010 12:13 pm
Location: Darkest Suffolk UK
Contact:

GCX buffer and reverse wah issue

Post by bettsaj » Fri May 24, 2019 8:19 am

I won't go into the whys and wherefores of the reverse wah effect, we should all know the history of this, Gilmour etc etc. but I have an issue that hopefully some techies might be able to find a solution to. Although this isn't todo with a GCX issue per se, I think the GCX buffered input is affecting how the wah pedal is reacting. Let me explain....

My guitar rig is quite substantial, a stereo rack with a switching system. My wah is a modified Area 51 conversion in a Dunlop enclosure. I wired a toggle switch to the enclosure so I could switch the inputs and outputs around for producing the seagull effects in Echoes (I play in a Floyd tribute). This all works fine when I plug the guitar straight into the wah, and then into maybe some other effects then into the amp. No problem, i can switch between wah or seagull effect at the flick of a switch.

Now onto my problem..... i had better explain the signal path...

The guitar is plugged into the front input of the Voodoo Labs GCX switcher (this is a buffered input), I then have various effects in loops 1 thru 6. The output of loop 6 goes to the input of my Wah, the output of the wah goes to the input of loop 7, I then have a boost pedal in the a send/return of loop 7, the output of loop 7 goes to my JMP1 pre-amp, and the signal from the pre-amp then returns to loop 8 input. I then have a TC G-Force in the send/return of loop 8 before the output of loop 8 goes to my power amp.

When I switch the seagull effect on i get nothing. I think it's a buffer issue, I read somewhere ages ago that the seagull wah effect doesn't like a buffered signal. This is why it only works in wahs with no input buffers on them. I suspect it's the buffer in the GCX that's causing the issue, but is there a way around this? would a line driver in the actual wah help, that's effectively a buffer??

In this video is a short sequence of a pedal similar to the one that Pete Cornish made for Steve McElroy of the Aussie Floyd... There's a line driver in this pedal, so I suspect what he's done is basically built a wah circuit into a box with a line driver.... but would this circumvent any buffers in Steves guitar rig??

I could run the guitar straight into the wah then into the GCX input, but would want to utilise the buffered input on the GCX which i don't think I can do from the rear as I have a wireless receiver plugged into the GCX. Also I have the wah wired into the GCX so that I can use it whether I use the wireless or cable.... I don't have to alter any cabling.

https://www.youtube.com/watch?v=U6XKC2bqWe4
"My technique is laughable at times. I have developed a style of my own, I suppose, which creeps around. I'll never be a very fast guitar player."

David Gilmour

JohnClark
Posts: 7357
Joined: Tue May 05, 2009 2:33 pm
Location: The Lab

Re: GCX buffer and reverse wah issue

Post by JohnClark » Fri May 24, 2019 11:10 am

I suppose the first test would be to plug your Guitar directly into Loop 1 Input, that way you can tell if its just the GCX Buffer or if any of the six pedals also cause this problem with the backward wah. Also, I'd test if the backward wah is happy with the wireless by connecting the output of the wireless directly to Loop 1 In.

Running the wah backward is a pretty if'y setup to begin with since it was never intended to be used this way. It's basically a studio trick that was already on the edge of failure... but just happened to sound cool, and was really only discovered due to a oops'd connection audio in the first place. That it mostly works in this rig as much as you say is sort of surprising to me ;)

Anyway, if it turn's out that it is only the GCX Buffer the backward wah doesn't like, maybe you can patch the buffer into an unused GCX Loop and bypass it when you want to switch to the backward wah.
------------------====Cheers!====------------------
Image
---------==Voodoo Lab Magician & Tech==---------

bettsaj
Posts: 234
Joined: Fri Jun 11, 2010 12:13 pm
Location: Darkest Suffolk UK
Contact:

Re: GCX buffer and reverse wah issue

Post by bettsaj » Sat May 25, 2019 12:14 pm

John, the backwards wah won't work with a wireless... It has to be hard wired, so on the occasion that I want to use the reverse wah i use a normal guitar cable plugged into the front input socket of the GCX.
"My technique is laughable at times. I have developed a style of my own, I suppose, which creeps around. I'll never be a very fast guitar player."

David Gilmour

Post Reply