Midi Pedal Board

[bass_dinger]

I recently won an eBay auction for what was labelled as an Elka organ pedal board.  Those of you more observant than I was, will have spotted that it has a 6-pin male midi plug, rather than the traditional 5-pin male midi plug.         

 

 

A little research suggests that there is no such thing as a 6-pin-DIN female to a 5-pin-DIN plug, so I need to create a 6-to-5 converter.  

And a little more research suggests that it is not an Elka pedal board that the seller advertised, but a General Music model, perhaps a GEM WS2 Keyboard Workstation add-on, made in Italy ( see here 

 

 

 

 

I was considering taking the 6-pin output of the footpedal and connecting it to a 5-pin, using two sockets (6-pin, and 5-pin) and a box to mount them into, and 3 lengths of wire to solder to the tags.  However, without knowing what signals the 6-pin outputs, I can't do that. 

 

Can anyone advise?

 

  

 

 

 

 

 

 

[bass_dinger]

I just found the circuit diagram for the 6 pin DIN input to its host keyboard.  I am none the wiser, and £21 poorer.  I am guessing that this is not a midi foot pedal. 

 

However, I am still positive: I may be able to fit some magnetic reed switches and a midi signal generator device into the pedalboard.         

 

 

 

[BassTractor]

1 hour ago, bass_dinger said:

I am guessing that this is not a midi foot pedal. 

Yup. Very, very unlikely to be a MIDI pedalboard. Just a typical brand-specific or semi-brand-specific pedal set. Those came with a wide variety of plugs and systems, though I don't remember the specifics. One of mine for example had a 27 pin connector.
 

[bass_dinger]

So, do I have a mis-sold item that allows me to request a refund? 

 

Or an inexpensive, neat and tidy pedal board to which I can easily retrofit a midi device?

 

Let me sleep on this question...

[BigRedX]

If it was advertised as a MIDI pedal that you can legitimately ask for a refund because it is not one. 

 

I you want to tinker, then it might be possible to convert it but that will very much depend on your soldering skills electronics knowledge and how much time you want to put into it as project.

 

BTW MIDI leads despite using 5-Pin DIN connectors only use 3 of the conductors - the centre pin for earth and the two pins immediately either side of that for the data signal. The other two pins are unused.

[bass_dinger]

https://www.basschat.co.uk/topic/457140-doepfer-mbp25-midi-bass-pedals/

 

This thread touches briefly on the subject of adding midi capabilities to a pedal board.

 

And of course, the pedals will (should) already have electrical contacts (on-off switches), so I won't need to add magnetic reed switches. 

 

 

[rwillett]

Personally speaking, I'd go for an eBay refund. You can spend a lot of time and money trying to get it to work or hacking something together. 

 

If you like the challenge, go for it, but you could easily lose 10-20 hours just trying to figure it out. 

 

I'm not demeaning your talents here but being realistic. I know what it's like as I love a technical challenge and waste too much time and money doing something that I shouldn't.

 

I now price my own time up and add that to the costs. So if I think something might take 10 hours and I think my time is worth £20 per hour, is it worth me spending £200 to fix it? I make exceptions for learning activities, as I think that learning is always good. Learning not to do something is valuable as well. 

 

YMMV

 

Rob

[Huge Hands]

Looking at that circuit diagram you posted, your pedal already does some sort of combining and sends the signal out as a "serial data" stream.   Whether that be a MIDI type stream or (more likely) an analogue variable voltage kind of thing, is anyone's guess.  I'm guessing it is not MIDI as I can't see a return comms connection on the drawing - unless it is send (MIDI OUT) only. 

 

The Thomann one you posted has a wide ribbon cable connecting to the MIDI module, which would suggest separate contact connections for each note pedal. if you wanted to do that with yours, I guess you would have to cut in further up in the pedal board circuitry before it turns them into one serial line?

 

To me, your drawing looks like it is for the organ end, and if so:

 

Pin 1 - Ground

Pin 2 - Ground

Pin 3 - Connection for separate volume pedal which I assume plugs into this pedal board on its way to the organ?

Pin 4 - Not Used

Pin 5 - 9v supply from Organ

Pin 6 - Serial data out of pedalboard to organ

Pin 7?   I assume this is chassis connection of the organ socket to ground?

 

As there is a separate connection for serial data and volume pedal, this suggests to me that the transmission medium is not MIDI.

 

I'm happy to be schooled by the electronics whizzes on here if I'm wrong as I don't read circuit diagrams very often any more!

 

 

Edited 8 hours ago by Huge Hands

[Hellzero]

This is indeed absolutely not a MIDI pedal at all as the typical MIDI connector is a 5 pins DIN type (there are a few others too like XLR, TRS, USB, 13 pins DIN, mini MIDI, ethernet MIDI, ... but no 6 pins type).

 

It's the pedalboard designed for the GEM WS2 with a 6 pins connector sending serial data to the main keyboard.

 

Here is the female connector on the GEM WS2:

 

 

That said, those pedalboards are quite rare and putting it back for sale with the right description will certainly put over £21 in your pocket, so you eventually made a good deal.

 

Here's the service manual for the GEM WS2: https://www.deepsonic.ch/deep/docs_manuals/gem_ws2_keyboard_workstation_service_manual.pdf

 

And here all you need to know about this MIDI protocol: https://en.wikipedia.org/wiki/MIDI

[bass_dinger]

2 hours ago, Hellzero said:

That said, those pedalboards are quite rare and putting it back for sale with the right description will certainly put over £21 in your pocket, so you eventually made a good deal.

 

If those pedalboards are genuinely rare and desirable, then it would be a shame to hack it about, even to modify it for the more useful midi configuration.  However, I don't see any for sale on-line, and the matching keyboard is perhaps 35 years old now - so they are either super-rare, or so obscure that they are no longer wanted by punters.  

 

I am impressed that you managed to find a clear photo of the rear panel!         

[Hellzero]

It wasn't that difficult, as it's an Italian brand, I checked Mercatino Musicale (the Italian musical instruments secondhand website) and here it is: https://www.mercatinomusicale.com/mm/a_gem-ws2-keyboard-workstation_id7475222.html

[Hellzero]

And another one, even more expensive: https://www.mercatinomusicale.com/mm/a_gem-ws2_id8295361.html