Can you describe what you would like to do?

I think its good to figure out what exactly you're trying to do because "similar" - we would say yes. You can either use fixed note arpeggios to map one key to several other keys. Or you could "eat up" multiple PARTs and layer them so when you press a key different notes are simultaneously played. In both cases you would note limit to a single note if mapping one note was what you were after.

So in the narrow scope that you have one trigger note - there are multiple ways to have a similar outcome.

If you have more than one trigger note - then the result will become less similar as Mainstage allows for wildly different mappings for each input note while arpeggios and multi-PART layering do not necessarily give you this.

There are other tricks you can do - but there is not a 1:1 mapping of what Mainstage chord triggers can accomplish on MODX. "Similar", perhaps. The devil is in the details of your requirement. You may very well be able to get to your destination - or your requirements may overwhelm what's available (or the resources you want to consume).

The other option, certainly, is to have some sort of MIDI-connected device like an iPad, PC, or Mac that does something similar but is not Mainstage.

Thanks for your input.

As an example I am trying to achieve the following:

Play B note and it would play Bm7
Play C note and it would play Cm7
Play C# note and it would play C#m7
Play D note and it would play F#m

Since they are all (except for D) the same root note that you press with added intervals to form a minor 7th chord - this can be done with ARPs fairly well for B C and C#. D is different - so you couldn't use the same ARP to make pressing D result in an F#m. You could add a second PART - a duplicate of the one playing the chords - and have a different ARP handle just the "D" key and its F#m chord.

Chord PART #1 - note limit to B through C# and assign the same ARP. There are sort of time-based limitations to what ARPs do. They do not always "play" transparently say if you want it to just add notes and play exactly what you do. At least not and follow your notes. The main issue is going to be playing legato. The arpeggiator doesn't see you retriggering an ARP until NONE of the keys in the trigger range are pressing. If you play legato - MODX thinks the second legato note is an extension (part of) the 1st note. You therefore cannot play legato and have the ARP follow you as if the legato notes were all roots. Note that "Org Note" works best. What I did to generate the user ARP was pressed the record button under superknob (the one with the round dot) then pressed the play button. I have a 2-measure count in. I waited for that - then played 4 beats of a Cm7 chord (C Eb G Bb). Then I pressed the "stop" button. I pressed the "Song Name" of the MIDI recording I just saved which brings up a menu on the left-hand side. On this menu I selected "User ARP". Then I made sure the ARP type was "Org Notes" instead of "Normal" or "Fixed" and saved the ARP.

Chord PART #2 - note limit to just D and use a different ARP that plays fixed note F# A C#. Creating this ARP is similar. You can either use Org Notes or Fixed. It doesn't matter since only one key is triggering.

If playing legato is going to make this approach not work - then you would have to layer different PARTs.

This takes a lot of resources - and since you have two different chord types - it "doubles" the resources. For notes B-C#, since these are all the same I would setup this by making two duplicate copies of a single-PART instrument (such as CFX Stage, for example).

PART 1 (CFX Stage) would be the root.
I would copy PART 1 to PART 2 (so CFX stage is also in PART 2)
... and copy PART 2 to PART 3 (so CFX stage is also in PART 3).
I now have enough to build a minor 7th chord - because I can leave out the 5th. And since this takes more resources, I'm going to cut back where I can.

PART 1 I leave alone. It plays root.
PART 2 I go to Common -> Part Settings -> Pitch and change "Note Shift" to +3. This supplies my m3 (minor 3rd)
PART 3 I go to Common -> Part Settings -> Pitch and change "Note Shift" to +10. This supplies my m7

Now I can play B through C# and hear natural sounding Minor 7th chords. For AWM2, there are other ways - but they all "stretch" the sample and do not sound natural. Some sounds may tolerate this - some, like CFX stage, do not.

For the D - I would have to utilize another 3 PARTs and "Note Shift" all 3 in order to end up with F# A and C#.

Finally, I would note limit PARTs 1-6 such that PARTs 1-3 were limited to just the B, C, and C# and then PARTs 4-6 were limited to just the "D" note.

That's a lot of resources to burn.

If you are using FM-X (not AWM2 meaning samples) - then you could just add carriers within a single PART which were pitch shifted. Then, depending on how many operators your sound takes to begin with, you could end up with a solution that plays all notes (B,C,C# minor 7th and F#m) properly using only two PARTs instead of AWM2's 6. I won't get into that because the final solution depends much on your starting algorithm and utilization. FM-X pitch shifts "better" than samples because it is complete synthesis - so you can do more with less generally.

What a great explanation!

Thanks - will definitely try this!

This would be a really cool feature, though. If the song is really repetitive, it'd be nice to not put those chords on single notes. Lazy, but nice. 😀

I know that this is an old thread by thought I'd add a work around.

I am using an Ipad connected to the MODX8 and the app Chord Poly Pro works really well as a midi controller with programmable pads for cord control.

you can even set it to channels 8-16 and then put additional sounds on that would not require Keyboard Control - thus freeing up parts 1-8 for sounds you need access to