Phantom powering a Liquid Foot 12+ (WARNING)

greiswig said:
I'm still trying to talk to FAS about a good solution for my individual unit to get it back in working order without voiding the warranty.
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Maybe wait for your next holiday period of gap in gigs/recording and send it back then? I can understand not wanting to having down time with the unit. But at least all the important stuff still works :)
 
javajunkie said:
If the is the rocktron cabe, not really. It only has 5 wires so no 2 way communication with axe-fx if you use the liquid foot. I hacked together a cable just like that but with a MIDI cable that had 7 wires
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OH! So it's a 5 wire cable with a 7 pin out head! Yea, I accidentally peeled back the cover on the RDMH900 cable with the dongle end & saw it's really just a pigtail soldered on to the pins with a female connector. Easy cheesy to replicate if you can get the cover off a regular ol 7pin.
 
javajunkie said:
If the is the rocktron cabe, not really. It only has 5 wires so no 2 way communication with axe-fx if you use the liquid foot. I hacked together a cable just like that but with a MIDI cable that had 7 wires
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You know that's what I thought, but it turns out that a basic 5 pin midi cable is all you need for 2 way communication with LF if you're powering the LF straight off the adapter. I had a call yesterday with Jeff and we programmed my 12+ with one standard 5 pin midi cable hooked up between Axe and LF, with the LF powered directly by the adapter. I guess the extra 2 pins are power only.
 
MikeyB59 said:
You know that's what I thought, but it turns out that a basic 5 pin midi cable is all you need for 2 way communication with LF if you're powering the LF straight off the adapter. I had a call yesterday with Jeff and we programmed my 12+ with one standard 5 pin midi cable hooked up between Axe and LF, with the LF powered directly by the adapter. I guess the extra 2 pins are power only.
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Right the axe-fx only needs 5 pins to communicate. A 5 pin cable can supply 2 way communication, but not 2 way communication and power. It needs the 7 pins for that. Which is why the rocktron cable will not work.
 
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LAYGO said:
OH! So it's a 5 wire cable with a 7 pin out head! Yea, I accidentally peeled back the cover on the RDMH900 cable with the dongle end & saw it's really just a pigtail soldered on to the pins with a female connector. Easy cheesy to replicate if you can get the cover off a regular ol 7pin.
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Which is what I did. I took the pigtail off the Rocktron and soldered it to pins 6 and 7 of the bestronics cable. Works like a charm.

Also, a very kind person built me a box that connect the a 5 pin to axefx, a 7 ping to the LF+ and 2 different sized barrel connectors for the power supply. I just velcroed it on my rack. No more plugging, unplugging the MIDI out of the Axe-fx.
 
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Update: my unit went back to FAS for repair. They initially authorized me to repair it myself, but when I tried I found that the solder pads the ferrite bead had attached to were vaporized. No way to repair it myself. So...again, be forewarned!
 
I have an Axe-Fx and Liquid Foot Jr coming. From reading both manuals of these units, I thought these were compatible. Will I be having any issues powering the Liquid Foot Jr through the phantom power jack with the 7 pin midi?

Thanks, Jim
 
jrg said:
I have an Axe-Fx and Liquid Foot Jr coming. From reading both manuals of these units, I thought these were compatible. Will I be having any issues powering the Liquid Foot Jr through the phantom power jack with the 7 pin midi?

Thanks, Jim
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If it is the Liquid Foot Jr, then no problems. If it is the new JR+, it should also work fine. From what I can tell, the problem comes when you put two LF+ together. FAMC sells a little box that works great and will supply the power without going through the AXE. The chain looks like this: 5 pin midi to box, power supply to the box, 7 pin midi to the controller.

I've been using LF+12+ with phantom via Axe-FX with no problems, but Jeff recommends using the box.

See 'ya,
John
 
FWIW, I'm powering my LF+12 using phantom power through the Axe-II and it seems fine.

According to fractal, the current ratings for the phantom power path is 1A.
 
gdgross said:
FWIW, I'm powering my LF+12 using phantom power through the Axe-II and it seems fine.

According to fractal, the current ratings for the phantom power path is 1A.
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The power supply that comes with the LF 12+ is 2A (at least originally). I believe he offers a 1A version for axe-fx II users now.
 
greiswig said:
As a PSA, let me tell you about a lesson learned the hard way. Nowhere on either manufacturer site will you find this, but if you attempt to power a LF 12+ through the MIDI cable in an AxeFX II, you will burn up a component in your AxeFX, and phantom will no longer be an option. The AxeFX can't support the amount of current the 12+ requires, but that's not noted anywhere in either manufacturers' documentation.

Jeff at Liquid Foot has a hidden option (on the order page, look under "Special Notes") for an external unit that will prevent this from happening. But if you're going to use phantom power, this is NOT an option, it's a requirement.

I have a support email in to FA, because I'd really like to not have to send the AxeFX back in for a repair.
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Don't know what you're talking about - I've been doing that for 2 months now. No problems whatsoever.
 
funny_polymath said:
Don't know what you're talking about - I've been doing that for 2 months now. No problems whatsoever.
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Are you using a 2A power adapter (which is what orginally came with the LF+). 2A blew mine.

This is why FAMC now has on option for adapter and power coupler for Axe-fx II.
 
javajunkie said:
Are you using a 2A power adapter (which is what orginally came with the LF+). 2A blew mine.

This is why FAMC now has on option for adapter and power coupler for Axe-fx II.
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I've been using the MFC adapter through the Axe-FXII with the LF+12+ with no problems. But since reading this thread, and wanting to daisy chain a couple of LF+'s, I ordered the new adapter you are referring to. The added bonus for that adapter is that it is really small, making it much easier to pack and plug!
 
Typically, a device only pulls the current it needs to, so a supply capable of 2A won't deliver that much unless it is asked to. Reducing the supply to 1A doesn't solve the issue, IMHO: the ferrite bead is rated at that, and if the 12+ pulls 800mA, that's awfully close to the limit. So although it may not blow immediately, it gives you virtually no wiggle room.

If you are daisy chaining devices like this last poster, you are doubling the current demand, so the 1A version of the power supply may not be able to keep up, and it also may be the last straw for that ferrite bead. Again, the two units might be asking for 1600mA, and the 1A power supply may be able to actually (briefly) deliver a bit more than an amp...and the ferrite bead probably won't like that. Best to either fix the ferrite bead with a heavier one or use the external box Jeff sells.
 
Hi
I got the RMM900 7-Pin Miodi Cable regular ( 7 - 7)
Then I read this..
Firstly I understand I got the wrong cable for phantom power to GCP? Should I have bought 5-7.
Or does this thread say I shouldn`t be useing phantom power at all?
 
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