The phantom power connector behind the Axe, what connection it is?


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The phantom power connector behind the Axe, am I crazy if I change it?

It's a 2.5mm DC plug, and all standard Boss stuff and all pedals I've seen use a 2.1mm version. Would I be mad if a change the connector to the more widely used 2.1mm version, so I wouldn't have to rely on the one and only suitable transformer I've managed to find?
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It's not to plug pedals into. It is for 9VAC not 9vdc power for pedals. Forgive me if this sounds a bit condescenting, but it doesn't sound like you are too familiar with what the purpose of that jack is. Typically, midi controllers run on 9VAC. Typically, those jacks are 2.5mm by design so as not to have 9vdc plugged into where 9vac should go. I'd suggest a thorough reading of the manual of both your controller and the AFII before you go doing that.
Nonono, I run my controller through phantom from there, the only trouble is the rare connector type, which I feel would be more useful and gig-proof if it was the more available 2.1mm version.
2.1mm is the standard for DC. 2.5mm is the standard for AC. The phantom power jack is designed for AC, hence the 2.5mm jack. I would strongly recommend against doing this. It also voids your warranty.
Both my controllers run on DC, I guess running DC through it doesn't harm anything?
Both my controllers run on DC, I guess running DC through it doesn't harm anything?

There's the rest of the story. Honestly...I'd build an adapter to deal with this rather than swap the jack out. The parts are cheap enough. 2.1mm barrel jack to a 2.5mm plug on the other end.
Both my controllers run on DC, I guess running DC through it doesn't harm anything?
I've run DC through it with no problem. If you are handy with a soldering iron, it's easy enough to cut the end off the power adapter you are plugging into the back of the Axe-Fx and soldering a new barrel plug, or just buy/make an adapter.
Well. Warranty aside, I actually mounted a 9v power supply inside my Axe Fx 2. I wired it up so that the phantom socket now outputs 9v whilst also sending phantom power through the midi pins 6+7. I have two 9v LED strips powered from the phantom power socket. One on the front and one on the back of my rack bag.

The result is that when I switch on my Axe Fx my midi controller also powers up and the my rack bag lights up both front and back. Very handy. Alternatively you could use the socket to power pedals in your rack.

Works for me. Just something to think about.
Hmmm, did the Ultra come with a 2.1mm jack? I didn't think they changed it. I have been using a Roland PSA with no adaptor on my Ultra for years. I didn't find any information about the size in the manual, I just tried and it worked. Still does...
i did take some photos ages ago but I think they might be on my old computer. I'm not going to pull my Axe Fx out of the rack bag and open it up just to take photos. It was relatively straight forward. You need to wire the power supply into the switch of the axe fx otherwise the 9v adaptor will constantly receive and output power to the phantom socket and midi socket.

I basically glued the 1.5A 9v adapter to the interior of the chassis so that the terminals were facing upward. I then soldered and heat shrank the terminals and connected them to the switch on the Axe Fx. The output of the adapter then is connected to both the midi pins 6+7 and the output socket (which I think I changed to a regular pedal type size). And hey presto! It works.

I did the same mod on my Ye Olde Ultra. I've never had any problems with it i often forget that I even had to do it. I wish there was some kinda stock solution for this. Anyway, I made my own solution.
I want to power Electro-Harmonix Super Switcher and five pedals with midi cable (phantom power) from AXE FX Ultra.
Can it be done? What should I do to make it work?
Be careful of the milleamps of the adapter, i think 1a or 1000ma (same thing i believe), my port in my II blew out and I think mine was rated for 1000ma to power my Axess FX1 and it went bye bye. Ended up wiring a jack into my rear patch panel, still use it that way.
For safe use do not go for more than 500mA in case of DC; over that you risk your unit. As you read above the supreme leader forbid (any DC use). Myself I use a 500mA supply over 7pin midi cable for my LG2 for 2 years already.
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