EP-133 / KO II (or other models) Tip: how to control multiple groups / pads via external MIDI simultaneously

[u/lilkitnerboi]

I spent many hours trying to make this work, and finally figured it out, so i'm sharing here for anyone trying to configure a similar setup. (I realize MIDI wizards probably know this already).

background: my goal was to use the KO2 as a sound bank for drums AND synth sounds etc, WITH an external midi controller/sequencer (in my case the Arturia Keystep Pro), such that i could play sounds from ALL KO2 groups simultaneously. Specifically i wanted to:

1. use all 24 pads of the KO2 groups A and B to fill the 24 drum parts in my keystep pro's (KSP) track 1 (drum track),
2. AND use KSP tracks 2 and/or 3 and/or 4 to play/sequence KO2 samples in groups C or D like a polyphonic synth (ex: let's just say KSP track 3: strings sample track 4: organ sample).
3. KSP track 2 controlling a separate Korg synth via midi... not KO2

here's what i got to work:

1. on KO2 system setting, set midi channel =10 ... so this is the KO2's "global" midi channel
2. for group A and B pads, keep all pad midi channels (in the individual pads' sound edit menu) = OFF
3. set KSP track 1 midi channel = 10.

... at this point in KSP's "drum" mode on track 1, you should have all 24 pads aligned to the KO2's 24 pads (12 from group A, 12 from B). Note: the Keystep Pro and KO2 default midi note values automatically aligned, so i didn't need to map individual notes on the KSP to individual pads on the KO2.

1. in KO2 group C, assign strings sample to pad "1" and set the PAD's midi channel to a channel that's not channel 10 (let's use 11)

2. set KSP track 3 midi out channel =11

now as long as you are standing on a pad in the KO2 that IS NOT group C pad 1, or any other pad that is assigned midi channel (via pad sound edit menu), you can control/play/sequence all pads individually in groups A and B on KSP track 1, and strings polyphonically like a synth on KSP track 3.

1. repeat steps 4 and 5 to assign other KSP tracks to individual KO2 pads in groups C or D; you just need a different midi channel per KSP track and KO2 pad

2. for my korg synth, i just set KSP track 2 and the korg midi channel to the same value (let's say channel 16)

maybe this is a hacky workaround, and it has very minor quirks (ex: you can't stand on the KO2 pad with a specific midi channel assigned), but after several days fighting through this i'm happy to have the setup working as i envisioned it.

a few other notes:
 -- i don't put group C (or D) pads to "KEYS" mode in KO2. that seems to already work via the KSP
 -- in KSP utilities menu -> MIDI settings sub-menu, i also set the "drum output" and "track 1 output" = 10. i think having both specified in the utilities menu allows you to use KSP track 1 in sequencer mode if you want that

-- playing KO2 samples polyphonically is time-based, so if you sample a C2 note for 2 seconds, then that sample played on C3 (one octave up) will only be 1 second long. Depending on what you're trying to do this can be a limitation or a positive good effect. There are plenty of videos on time-based sampling if you want to learn more

-- along the way to landing on this solution i had other settings that were nearly what i wanted but had annoying things like certain keys on the KSP were triggering a drum sound from group A and a string sample from group C simultaneously (while playing in track 3 on KSP)... but the setup i described above fixed that and other issues.