Setting up GCX for tri amp and FX loop solution

Q & A for building and interfacing your rack gear with Ground Control Pro and GCX-based systems.
Post Reply
Henrik Helgesen
Posts: 1
Joined: Mon Mar 18, 2019 10:45 am

Setting up GCX for tri amp and FX loop solution

Post by Henrik Helgesen » Mon Mar 18, 2019 11:04 am


I just accuired a Ground Control Pro, and two GCX units. I would like some help in making a schematic set-up in how to connect my devices. I´ve enclosed a pdf for a simple overview of my set-up- I want to connect three amps. I would like to control channel switch and reverb from ground control pro. Two amps have a standard switching system with mono jack, and the last has a midi controller unit. I have several stompboxes. Some, like wha, OD´s i.e. I want to have in the front of the amps. Other should be routed to the fx loop of each of the amps. Best thing would be to control them independently, so I could choose from using wet signal on the same amp I use, or as a dry wet configuration. I normally use two amps at the same time.
Voodoo lab GCX set-up tripple amp.jpg
Voodoo lab GCX set-up tripple amp.jpg (19.45 KiB) Viewed 1365 times

Posts: 82
Joined: Mon Sep 07, 2015 12:46 pm
Location: Australia

Re: Setting up GCX for tri amp and FX loop solution

Post by Marlboro05 » Wed Mar 20, 2019 9:12 pm

Hi Henrik,

I’m not sure you will be able to do it like you want with what you have here.

This is a similar setup that you may have to sort of do but you could use 2 of your amps as power amps, obviously you could do a wet dry wet setup if you have 3 speakers. ... werAmp.pdf

I’d supply to the amps with a splitter, then from the Amp effects sends, to the GCX to choose which amp you want on or off. Then have the signal going from the loop to the effects, then to the power section/sections that you want to use and or the dry amp.

With multiple amps you are subject to ground loops, best way for you is to get something like a Radial Shotgun which has isolation and phase correction to drive your amps.

What are your amps? I think you have a Marshall Astoria, a Bogner Goldfinger and a Laney L20H? You’d be abe to use a GCX to Switch the preamps of 2 of your heads and midi to control the other midi capable one.

Are the pedals the Strymon El Capistan and Flint? Both are Stereo so you’d be able to set them up as effects to 2 of the Power sections and use 4 loops on a GCX. These can be tuned on/off via Instant Access and can be turned on via Preset as well.

The Wah, Tubescreamer and I think it’s a MXR Phase 90 can go in front of the preamps with the Wah before the input for the GCX and the Tubescreamer and Phase 90 in a loop each, tuned on/off via Instant Access. These can be set to turned on with a Preset as well. You can keep these on the floor in a pedal board and control them that way to.

I hope this helps you a bit, if you can confirm the amps and pedals, I’ll attempt to do you diagram for you.

Cheers Brett
GCPro, GCX, Pedal Power 2+, Pedal Power AC.
And some other stuff.

Posts: 7437
Joined: Tue May 05, 2009 2:33 pm
Location: The Lab

Re: Setting up GCX for tri amp and FX loop solution

Post by JohnClark » Thu Mar 21, 2019 10:39 am

We can't really accomplish all the goals here at once. Individually we can do any of these things...
effects switching, sharing loop effects, amp selection, and amp function switching. But, doing all of this at once would likely take more loops than you have available with even two GCXs.
For instance, you can share effects between effects loops, but it would only really work if you were only ever running one amp at a time and even then just selecting which amp's effects loop is live would take at least four (maybe 6!) GCX Loops to accomplish... so it turns into a cable spaghetti real quickly.
We can select any of the three amps, and even allow for having any combination of them including all three at once, but then we couldn't share the effects between the amp's effects loops since the non selected loop would result in a muted amp.

When you say you typically run two amps at once, is there one amp that is always live and the other two are sort A/B'd or Off? Do you really need the delay and trem/reverb individually available for each amp? These effects typically just need to get out into the air and might even sound better if always ran to a dedicated amp in a sort of simplified wet-dry configuration.
A full wet-dry-wet rig as Malboro05 linked to would allow you to treat this as having three different preamp section to select between and use the power amp sections to create a stereo pair of "wet" cabinets with a center "dry" cabinet as a completely different approach to this.

Let us know what you think. We can hone in on a setup that works for you, I am sure!
---------==Voodoo Lab Magician & Tech==---------

Post Reply