Page 1 of 4

MIDI Controller Modification

PostPosted: 20 Dec 2012, 13:13
by Alexkidd
This has nothing to do with Cross, but you guys have been very helpful 'till now and i trust you.

I want to modify my MIDI controller. it's an M-Audio (aka Midiman) Oxygen 8. The mod that i want to pull off is replacing the key with arcade buttons and i have no idea if this can be done.
Do you believe it is possible?
Where and how should i solder them?

Some photos to help you help me:
Image
Image
Image
Image

Re: MIDI Controller Modification

PostPosted: 20 Dec 2012, 15:40
by Marxon
do it on your own risk:

shortcut this two pad with some wire momentary and see what happens. to get velocity sensitivness (keyboard) i only know circuits which generates voltage so short circuiting should not work. but your picture looks like "pad switches" like in tv remotes. they can be shortcuted.

key.jpg

Re: MIDI Controller Modification

PostPosted: 20 Dec 2012, 15:42
by MusicMeister
Without doing any testing at all my first reaction is that you may need a double pole double throw switch.

There are 4 pads for each key and it looks like they 'connect' on each keypress between the left and right.

I'd start my testing there.

Re: MIDI Controller Modification

PostPosted: 20 Dec 2012, 15:44
by Alexkidd
the four black pads are for velocity sensitivity.
with my arcade buttons i won't need velocity. and i don't want velocity

Re: MIDI Controller Modification

PostPosted: 20 Dec 2012, 15:55
by MusicMeister
The 4 black pads collectively are used for velocity.

Depending on the circuit itself, you may be able to use a single pad set as Marxon suggested, or you would have to short both sets of pads at the same time (guessing based on my own electrical knowledge) and just have it send 127 all the time as the velocity value.

But testing of the electrical circuit is needed to know for sure.

The mechanical is that the pads are shorted Left/Right. How the circuit handles one set of pads vs. two is up in the air and requires more testing.

Re: MIDI Controller Modification

PostPosted: 20 Dec 2012, 16:07
by Marxon
MusicMeister wrote:The 4 black pads collectively are used for velocity.

Depending on the circuit itself, you may be able to use a single pad set as Marxon suggested, or you would have to short both sets of pads at the same time (guessing based on my own electrical knowledge) and just have it send 127 all the time as the velocity value.

But testing of the electrical circuit is needed to know for sure.

The mechanical is that the pads are shorted Left/Right. How the circuit handles one set of pads vs. two is up in the air and requires more testing.

if my english would be better i would have said this too :mrgreen: :mrgreen: :mrgreen:

Re: MIDI Controller Modification

PostPosted: 20 Dec 2012, 16:59
by Alexkidd
i'll buy a multitester, ill make the test and i'll let you know.
PS: to see full pictures right click -> View image
Copy & paste link url for chrome

Re: MIDI Controller Modification

PostPosted: 20 Dec 2012, 18:03
by MusicMeister
Actually, you don't need a meter - you need a way to monitor the MIDI messages.

Drop the strip back on top, fire up the MIDI controller and only hit the pad at the top.

Then only hit the pad at the bottom.

Then hit both together.

Make notes of the messages being sent and adjust based upon that. :)

In short, if you don't get a message when you hit 'just' the top or bottom then you need to hit both at the same time.

At that point you would need a meter or scope to determine the signals being passed and if you could tie them together or if you need a double pole switch.

Re: MIDI Controller Modification

PostPosted: 20 Dec 2012, 18:22
by Alexkidd
i can't do this right now cause i'm back at my home town for christmas holiday, but i am sure that the top pads alone will send MIDI signal but not full velocity.

Re: MIDI Controller Modification

PostPosted: 20 Dec 2012, 18:24
by MusicMeister
If it's just the top pads for note on/off - then that's all you need. :)

But a quick testing will let you know for sure. :D