I read somewhere (possibly here?) that OP-Z was only able to trigger one sample on the MicroGranny, and additionally most videos I have seen of the OP-Z controlling MicroGranny has OP-Z only affecting one sample. This was upsetting to me, as it takes away some of the beautiful glitchy functionality of switching between samples on the MicroGranny.
MicroGranny has the ability to trigger the 6 samples in a single bank once you turn on the “TUNED” setting, and put your midi instrument output to the lowest octave range. However, when I put OP-Z in the lowest octaves available, for some reason OP-Z will not trigger the 6 presets it will only trigger the same sample on the MicroGranny in the lowest octave (usually resulting in no sound whatsoever). Finally today I read another post on this wonderful forum which explained that OP-Z Tracks 1-4 (Drum and FX) do not respond to octave changes, and previously I had routed MicroGranny to the Track 1 Midi Out. So I changed MicroGranny to accept notes from Channel 5 from the OP-Z and sadly nothing changed. It was still doing the same thing no matter what note or octave I changed the OP-Z to, it never triggered the 6 samples, just would play whatever sample I had selected last on the MicroGranny.
What worked for me is this. (NOTE: I am no programmer so perhaps there is probably a simpler way)
On the iPad I opened up AUM, and created a keyboard midi-input (KB-1) for my OP-Z via Bluetooth on Channel 5. So when I play the note on the KB-1 keyboard it will play the note on my OP-Z. My OP-Z is connected to the MicroGranny via a RetroKits RK-005, on Channel 5. I octaved down the KB-1 to trigger notes on my OP-Z on octave range C-1 and magically, C-1 and the next 5 notes up on the KB-1 triggered the 6 samples on the MicroGranny. I recorded a pattern and it works.
Whats crazy is that when I see the pattern playing on my OP-Z only the C notes light up, even though, different notes are obviously playing to trigger the 6 samples. Maybe this is a CC note thing? I have no idea. Just happy I was able to get this to work!