Gordius Little Giant - Two way communication & power in one cable

  • Hi guys,


    I did a little weekend project. It might be interesting for those of you who have a Gordius Little Giant.
    With the AxeFx (I owned & sold when I got the Kemper), it was possible to transmit power, MIDI In & MIDI Out in one 7-pin cable.
    Unfortunately, that's not possible with the KPA. I hate extra wires, so I came up with a little box that connects to the KPA via two regular MIDI patch cables.
    There's a DC barrel to connect the power supply for the Gordius. Power & signals are connectied to the LG via a single 7pin MIDI cable.


    For those of you who want to build one too:


    pins 2,4&5 to pins 2,4&5 of a 5-pins "MIDI OUT"
    pins 1&3 to pins 4&5 of a 5-pins "MIDI IN"
    pins 6&7 to a power adapter jack


    The pin numbering described in the Gordius manual, appendix B (p.141): http://www.gordius.be/LG_usermanual_v3_0_6.pdf


    Thanks a lot to Xavier from Gordius for his help...


    Enjoy,


    M.


    [Blocked Image: http://weilthing.com/KPA/Foto.JPG]

  • Pretty nice looking box for a weekend project.
    You would not like to see what a mess I would do with a project like this even if I would have a month ahead of me.


    I would be so mad at the point when I am ready to test and then fry my kemper :P

  • :)


    I connected the MIDI plugs first. Once I saw that it was working properly, I unplugged the power from the Gordius and connected it to my converter.
    The trickiest part was soldering the 7pin connector. It's pretty small...

  • Nice!


    I've got a Gordius LG2 which is powered by a custom made 5-7 pin MIDI cable...I miss the power of 2-way communication though.
    I assume you tested if you can have an entire stompbox/effect layout transferred to the Gordius?

  • From the Gordius manual, page 141:


    The 7/7 cable has a 7-pins connector at both ends, and has all 7 pins actually
    wired. So it is safe to use this cable with the 2-way communication option. The 7/5 cable has a regular
    5-pins connector plus female power jack at one end.
    It does NOT have pins 1 & 3 wired, so this cable can only be used to combine phantom power with MIDI
    OUT, no 2-way communication is possible with this cable.

  • Cool. I made a similar box a few weeks ago. I run a 7-wire cable from my rack to my LF+ controller. IIRC, my wiring is the same as yours.


    You'd think that this is a common enough task that someone would offer these boxes commercially. I spent about twenty dollars on materials. I would have gladly paid seventy or eighty dollars to buy one ready-made.

  • Nice... so I had a Little Giant and sold it as Xavier told me that he won't implement support for the KPA.... :(

    MJT Strats / PRS Guitars / Many DIY Guitars -- Kemper Profiler Rack / Kemper Remote / InEar

  • Cool. I made a similar box a few weeks ago. I run a 7-wire cable from my rack to my LF+ controller. IIRC, my wiring is the same as yours.


    You'd think that this is a common enough task that someone would offer these boxes commercially. I spent about twenty dollars on materials. I would have gladly paid seventy or eighty dollars to buy one ready-made.


    Same here, I would have bought the finished product if it was available. I think that if it would be made in Shenzen, with the MIDI plugs molded in plastic, you could make it for less than 10$ a piece.


    I was contacted via this forum if I could build one. The thing is that with ordering parts for just one more, it's too expensive. If I have ten orders, then I'll do them in one batch. Pricing tbd - current estimation is that it will be around the 80 dollars you mentioned.


    Nice... so I had a Little Giant and sold it as Xavier told me that he won't implement support for the KPA.... :(


    Almost happened to me too. I didn't because of the lack of real alternatives. I don't really like the Behringer FCB-1010, so I thought "Let's hold on to it until there's a pedal that actually does 2way communication" cause Xavier said that he's not going to implement KPA support, but came up with it a few weeks later. :thumbup:

  • I sold one of these via this forum. So I had to make a replacement for me. Since I had to set up a drill and all other tools which takes a few hours - I thought I'll make two this time. So if anyone needs one - I now have one spare to sell.


    Send me a PM if you're interested.

  • I purchased one of these little magic boxes from multivir1.


    He shipped it to me very quickly and he was amazingly friendly and helpful throughout all the process.


    The box looks very professional and built like a tank. It's really sturdy and compact - even more than I expected - which I love. It works like a charm.


    PS:
    For those who want 2-way communication between the KPA and the Little Giant and plan to use the LG with just ONE 7-pin MIDI cable together with a MIDI box like mine, you have to make sure that the LG MIDI out connector is set for 2-way communication. You can choose this option when ordering a LG.
    In case you already own a LG and you don't know its MIDI out configuration, if you use a 7-pin MIDI cable - with all 7 pins wired - and you don't get 2-way communication, then probably you'll have to set the LG MIDI out properly yourself by opening the LG and shifting the internal jumpers as described in the appendix B of the LG manual (pages 144 and 146 of the current version of the manual, v3.0.6)