Best Midi Interface for iPad stage


Any advice on the best simple 1-in x 1-out MIDI to USB 
connecting my Gordius midi controller and iPad.
I see a few likely options, and want the best

iConnectivity mio
Roland UM-ONE-MK2
M-Audio Midisport Uno

or any other recommended.
thanks for any advice, and happy holidays !!!


All of those but the FORE are excellent.  I thought all the Gordius controllers had USB built in?
If your Gordius doesn't have it's own power, you'll need the powered USB adapter for the iPad.  The iPad won't power the pedal from it's Lightning / USB C port.


Thank you.  I think that's what i need to know.  I assume the iConnectivity and Roland are similar.  I'm currently using a cheap one, and I don't trust it.  Just trying to remove weak links.

Yes, the Gordius does have USB, but I don't think it can be used to send MIDI control to change patches.  My setup is more complicated than my mind can keep - it amazes me that it works.  iPad (setlist) communicates back and forth to the Gordius (through MIDI in/out), and Gordius controls the AxeFX (other MIDI out).  USB port is used for updating config.  

I get an occasional freeze up, which is a little scary on a live stage, but i'm amazed it all actually works.  First step is to get a better interface.  

thank you !!!


On Thu, Dec 23, 2021 at 06:07 PM, sirnothing23 wrote:
Yes, the Gordius does have USB, but I don't think it can be used to send MIDI control to change patches
Hey Dan,

the LittleGiant can send preset changes through USB. In LG2ControlCenter you have a "Routing" tab where you can specify whether the programmed preset content is sent to MIDI OUT, to USB, or to both. Also for the MIDI received through MIDI IN you can choose to have it forwarded to MIDI OUT, to USB or to both. 
The built-in MIDI-USB interface actually has 3 MIDI-USB ports. Port 3 is a dedicated port for patchdumps and firmware updates. The 2 other ports act along with the 2 MIDI IN/MIDI OUT connector pairs as a 2x2 MIDI-USB interface. 



Thanks for the reply.  
I need the Gordius to RECEIVE (and send) MIDI via the iPad.  Can it receive?

To explain:
I send a MIDI message from Gordius to the iPad (BandHelper app) for "next song".
iPad (BandHelper) sends a MIDI message for the song to the Gordius (to call Gordius preset or patch list)
Gordius sends MIDI for patch on AxeFX (either scrolling patch list, or stomp box on Gordius - depending on song). 

Maybe I'm trying to do too much too fast, and i need to add some latency when sending back to the Gordius from iPad?
It's working ok this way, but the Gordius freezes occasionally.  I need to diagram the data flow every time I think about this setup.  I keep wondering if there's a better way to do it, like with the Tiny Box, but I don't think so, and this works - almost always  :-) 

Thank you !!!!
Merry Christmas.


On Fri, Dec 24, 2021 at 02:55 AM, sirnothing23 wrote:
I need the Gordius to RECEIVE (and send) MIDI via the iPad.  Can it receive?
It can receive, but I just checked the sourcecode and you are correct: the functionality you use to remotely control the LG2 from BandHelper is only available on the MIDI IN connector, not on USB. Therefore you will indeed need an extra MIDI-USB interface. 
The occasional freeze has to be some kind of "MIDI loop". For instance if there would be one LG2 preset which by mistake sends a command to BandHelper, which triggers an "LG2 next song" which again sends that command to BandHelper...  2-way communication always introduces the risk for such loop.     


Again, thank you - for many many years of support !!!

I can't reproduce the problem at home, even with the same setlist and setup, so I assume it's nothing the LG2 or Bandhelper are programmed to send.
As I recall, it happens on stage - in a crowded and very digitally noisy environment.  

I'll turn off Bluetooth and Wifi on the iPad (i don't need them).  I have a better interface coming (though I don't suspect the interface).
Maybe the iPad is sending some data to the USB MIDI interface.  I've never seen anything odd in the MIDI log, but it's like my old 944 - never fails when i'm in a place to troubleshoot  :-)

Let me know of any other ideas.

Cheers and Happy New Year !!!


On Sat, Jan 1, 2022 at 03:09 AM, sirnothing23 wrote:
Let me know of any other ideas.
If the issue only occurs "in a noisy environment" then it might also be related to some power issue - ground loop or something. I know the LG2 may freeze if the used power adapter is underrated, so maybe excessive noise on the power input might also cause a freeze even when the power adapter is well within specs. It might be worth trying some alternative power adapters, although I suspect you already have ruled that out. Also, if you don't use the USB during performance make sure you disconnect the USB cable. MIDI connections are opto-isolated to avoid ground loops, but USB isn't, so a connected USB cable might have its influence in a noisy power environment.


I'm glad you prompted me to check power.  Not sure how well i'd researched this, but great to know, and something else to try !!

I'm using a Voodoo Lab Pedal Power 4x4.  
It has 400mA and 100mA at 9V / 12V outputs (isolated)
LG2A manual specifies 500mA at 9V.  I recall you saying that it has a forgiving regulator.  Certainly built like a tank.  

I've been using a Y-cable to parallel a 400mA + 100mA.  Higher current / parallel outs is not mentioned in the manual, but Voodoo just confirmed it's ok.
I'll Y (parallel) two of the 400mA outs, to be sure.  Seems like overkill, but lots of stuff loading circuits - i'm sure there's line fluctuations.  

I don't have much else on the power supply:
  • 3 LEDs in a switch box
  • 1 small 10mA (10-30V) mic preamp (i think i've been running it on 9V)
  • Tinytune Kliq tuner pedal (no current spec, but pretty sure it's well under 100mA).  
One other thing - i might have been charging the iPad via lightening Apple camera kit connection when this happens.  I could eliminate that too.
So between 3 or 4 changes (1 - disabling Bluetooth, 2 - wifi on iPad, better USB/MIDI interface, 3 - power), maybe it's resolved.

Fingers crossed, and thank you again for the help !!!


While paralleling the power bricks does work, it's not exactly ideal.  It gives you two points of failure instead of one - never a good thing.  I'd urge you to get a single power supply for them, or chain a 12v to 9v converter from a larger 12v supply (something like

Along with that, a little advice:  Anyone that has any kind of performance gear will save themselves a LOT of money and headaches if they learn basic electricity (how to use a multimeter) and soldering.  Both are easy, and the knowledge will let you fix your own audio cables and power adapters or even make them yourself.  Oh, and electrical tape is NOT a permanent insulator!  It will degrade and fall off eventually.  Use shrink tubing or (not really recommended because it's messy and hard to remove) "liquid electrical tape".  For larger connections and AC 'mains' power, 'rubber tape', or silicone self-fusing tape, is much better than plain electrical tape.


Thanks for the input !!   Greatly appreciated.
I could run another supply for the LG2 but the Voodoo Labs 4x4 should be ok supplying 500mA - 800mA - nice toroidal transformer and isolated supply.    Technically, I'm not paralleling 2 bricks.  I'm paralleling outputs from the same brick.  It's designed to do that, and they actually sell the Y adapter to do it.  Very nice power supply - allows doubling voltage and current (series or parallel).  

I hope I didn't say anything stupid, but wouldn't be surprised.  A step down from 12V to 9V should work too.
12V x 400mA = 4.8 W  (supplied)    
9V x 500mA = 4.5 W (required by LG2)
But isn't that also 2 points of failure?  :-) 

Everything on this rig is road-worthy, heat-shrinked, properly soldered, secured, and all power cables are stock, not handmade. 
I did build a custom snake that carries signal and MIDI.  It's from pro snake cable, shielded.  I also built the mic preamp, and routing switch box.  I don't suspect anything i build, but i probably should  :-)     It is a complicated setup, and many places for failure.  Amazing that it works !!

MIDI loop seemed likely, but i think i eliminated that possibility.  I would believe AC line fluctuation, so i could do some tests there.  

I really appreciate the advice !!!


Yes, it would be two points of failure as well.  I obviously didn't know it [the 4x4] was designed for it, or that it was so well made to begin with.  I was envisioning two cheap wall warts paralleled together! :-P  Awesome job on the custom stuff!  If you know what you're doing (and it seems like you do), custom cables and power can be more better than commercial/stock stuff.  MIDI uses bipolar signalling, as you may know, making it fairly immune to noise from other stuff near the cables.  As long as everything's shielded, even amplified audio feeds to high power speakers shouldn't bother it.

AC line noise could be an issue, but I'm kinda doubting it. USB is also bipolar, so it'd have to be a really large transient.  I keep coming up with things that could be the problem, but all of them would require MIDI being looped around somehow, like the LG echoing iPad MIDI to the AxeFX at the same time the LG is sending a patch to the Axe, or the Axe's MIDI THRU being connected back to the LG.  The LG manual says, "The MIDI IN port can be used to merge an additional incoming MIDI signal with the messages generated by the Little Giant." This would cause the first case I mentioned, so unless you're using that feature it should be turned off... but you probably know that already.  Try the delay thing, just a couple hundred milliseconds before sending the patch to the AxeFX.  It can't hurt, and might just be the magic that makes it work for you.


This is helpful.  I need a diagram at this point to even begin to sort the data flow.
I don't think LG should be echoing iPad midi to Axe (see below).  But I surely could be wrong.

To FCB       ------------------> iPad In
From FCB   (empty)
Midi Out      ----->  AxeFX       
Midi In         <------------------ iPad Out
USB            (empty)

LG Routing:
Midi In is NOT routed to Midi Out or USB 
LG switches are routed to Midi Out and USB   (hmmm.  Why am i sending LG switches to USB?  But nothing is connected).
NOTE:  No slave controller is enabled, so FCB in/out act as second regular Midi in/out port.

LG Filtering:
Midi leaving the "To FCB" port = Ch. 3  (iPad - midi soft thru NOT enabled in Bandhelper)  
Midi leaving the "Midi Out" port = Ch. 1 (AxeFX)
Midi Remote Control channel = Ch. 3

I'm wondering why i'm not using the "From FCB" port for iPad out.  hmmm.  Would that be safer?  or equivalent?  maybe i should try that?

I might be able to figure out how to delay Midi coming from iPad:
There's option to send Midi presets together with delay between <value in sec>  (currently off)
And and options for preset order with delay between <value in sec> (currently order is:  Control Change - Program Change - Raw Midi - Standard Midi file)
iPad/Bandhelper should just be sending Control Changes - Controller / Value, e.g. 52 / 006  to select a Bank with default preset group, some with patch list. 

I don't see a way to delay patch change on the LG (to Axe), and not sure why that would help (though this is all beyond me).
Holy crap, this is confusing, incredibly powerful, and flexible.   There might be a "better" way to do this, but this is (again) why I appreciate the engineering and support of Ossandust and communities like this.  whew.

Thank you !!!