Question about Fractal, Phantom Power, and Midi Thru


New Member
Hi everyone!

I'm looking to upgrade to a GT controller with my Fractal setup and have a few questions about setup and midi.

Some backstory: on my pedalboard is a Fractal FM3 and some pedals like the Eventide H9. I would like to set things up with mainly controlling everything with the GT but when space might be a concern just run things utilizing the midi block within the FM3(these would be a handful of different presets that would not contain a midi block when using the GT). In order to have this work without changing settings within the Fractal each time I would need the FM3 Midi Thru turned on.

1) Does having the FM3 midi thru turned on effect the Fractal/GT integration?
2) When utilizing the RJM phantom power box, am I able to put a Quadra Thru in between the FM3 midi out and the RJM phantom box without effecting the Fractal/GT integration?

Thanks for your help!



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MIDI Thru will likely be the only reason the above won't work. That's going to cause a MIDI loop, where everything that comes out of the GT will be sent right back to the GT. That's going to interfere with the normal GT<->Axe-Fx communication.

If you replaced the phantom power box and Quadra Thru with our MultiBox, that would work better. The FM3 in and out would connect to the box, the GT MIDI out would also connect to it, then you would use the remaining thru port on the MultiBox to go to the H9.

If you didn't use the GT, you would have to move the connections around, connecting the FM3 MIDI output directly to the H9 MIDI input (or the Multibox MIDI input).
1) Does having the FM3 midi thru turned on effect the Fractal/GT integration?
2) When utilizing the RJM phantom power box, am I able to put a Quadra Thru in between the FM3 midi out and the RJM phantom box without effecting the Fractal/GT integration?
First, a disclaimer: I don't work for RJM. I am just a customer, but I am a big fan of the MMGT and help set systems up for other musicians. So, if anything I say is crazy or wrong, that's on me :)

I don't use exactly this configuration, but I have an AxeFX III and FM3, plus a few MMGT control pedals, and I have used the Phantom Box. So, here are my thoughts on your questions. See the attached diagram for reference.

MIDI Command Flow
Based on what you are describing, you want to be able to use either the MMGT or the FM3 as the overall system controller. If I understand you correctly, you are saying that the direction of command flow will always be one of these two scenarios:
(1) MMGT -> FM3 -> H9 (and whatever else is on your board)
(2) FM3 -> H9 (and whatever else is on your board)

If the MIDI command flow is limited to scenarios #1 and 2, your GT / FM3 setup is going to be simple. You only need one 5-pin MIDI cable between the devices, from GT MIDI OUT to FM3 MIDI IN.

Phantom Power Box
The Phantom Power Box has MIDI IN and MIDI OUT jacks, along with a DC power input (for the GT) and a 7-pin MIDI jack for connection to the GT. As long as your MIDI flow matches the description in scenarios #1 and 2 above, you can use the Phantom Box to carry power / comms to the GT via a 7-pin MIDI cable, but you wouldn't have anything connected to the Phantom Box MIDI IN port.

The FM3 MIDI OUT port can be configured as for "soft MIDI THRU", which merges data received at the FM3 MIDI IN with any internally generated MIDI. For those settings where stage space is limited, and the GT isn't present, the FM3 will stand in as your pedalboard controller. As you noted in your post, you'd need to create alternate versions of your FM3 presets with MIDI payloads to control the other devices on your board. When the GT is present, its MIDI commands flow to - and through - the FM3. If the GT is only sending MIDI, then there will be no issues.

OK. Let's talk about the more difficult scenario...
You could set up your system such that either the GT or FM3 can act as the main controller, and have them both stay in sync regardless of which device sends commands. In other words, you could switch presets on either the GT or FM3, and the other device would respond to that command. To do this, you'd connect a MIDI cable from the Quadra Thru MIDI OUT / THRU to the GT MIDI IN (either via the Phantom Power Box MIDI IN, or directly to the GT MIDI IN), and make appropriate MIDI configuration settings. There is a potential here for a MIDI loop, as described in the post above [as we learned from the Ghostbusters: don't cross the streams!]. Setting up your rig this way will make it more difficult to program and troubleshoot, so it's up to you whether the results would justify the effort.

What I Recommend
First off: keep it simple by having the MIDI flow in one direction from GT->FM3->H9 and the rest of the universe.

For the rest of the configuration, you'll probably be tempted to use the GT as the main controller at all times. Its power and versatility make it worth the extra 2 square feet of real estate. That said, for the option of a smaller setup, go with the FM3 and its MIDI payload capability.


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