Jason, if we think in terms of signals:

What does the MODX/Montage send when things are changed in the screens of sound editing?

Like everything Synth, I am a novice, but not incapable of learning. I am new to MIDI also.

In the Data List, Page 219-220 are listed FM-X MIDI Parameter Change Tables.

Since this appears in the "Bulk Dump Block" Section, I assume these Tables are related to SysEx, not CC.
Please can you confirm this is SysEx?

The good news is, every single parameter is therefore MIDI controllable. The same goes for all other parameters, AWM, Drum, Motion Sequencer, LFOs, Filters etc.

NB: Hopefully, its all "Real Time" changes that can be made on the fly. In contrast to "Stop/Hands-Off, Apply Update Script, Wait for upload and confirmation, Hands-On, Test". (I would like to use Arpeggios to keep the FM-X inplay whilst making changes).

What I'm currently wondering is.... MorningStar Midi Controllers. I want to get one of these for my Guitar rig, they can work standalone in that sense. But, they can also "Middle Man" with "Expression" Midi Controllers... e.g. a Simple MIDI Foot/Expression Pedal in the case of Guitar.

So maybe a MorningStar could "double up" on value to me. I am thinking it could interface between my MODX and a simple dumb MIDI Controller like the AKAI MIDIMIX (or Dragos suggested StudioLogic Mixface) . I obviously need to research more.

What makes the Morningstar so attractive is it has a very user-friendly PC/MAC based editing suite, that only needs to be done once (per intended functionality). This includes CC to SysEx conversion (example for Strymon... specific setting of Delay Time in milliseconds which can only be done with SysEx, not CC).

I think if I had to start DIYing my own "Apps" and fudging functionality it would be a case of diminishing returns for me. There are a few public domain DIY MIDI apps that I tried for Line6 POD, and Strymon "Patch Library" organisation, but I found them very clunky, buggy and time consuming. I have no reason to believe I could design any better.

All food for thought.

Antony, will research the Morningstar. From the way you describe, it sounds perfect!

Jason, if we think in terms of signals:

What does the MODX/Montage send when things are changed in the screens of sound editing?

Nothing.

Detail ...

When you make a parameter change - the instrument doesn't advertise the change externally. By this I mean there's no interrupt signal going out. Nothing pushed. If you want to get a sense that something has changed from the outside you need to poll the edit buffer and compare against your last sample of the edit buffer.

All we have to examine are the MIDI ports. You can connect a USB cable and have a MIDI monitor dump ports 1,2, and 3. You won't see MIDI output (from MODX/Montage) when values change at least as a direct consequence.

So maybe a MorningStar could "double up" on value to me. I am thinking it could interface between my MODX and a simple dumb MIDI Controller like the AKAI MIDIMIX (or Dragos suggested StudioLogic Mixface) . I obviously need to research more.

What makes the Morningstar so attractive is it has a very user-friendly PC/MAC based editing suite, that only needs to be done once (per intended functionality). This includes CC to SysEx conversion (example for Strymon... specific setting of Delay Time in milliseconds which can only be done with SysEx, not CC).

The ModDevices Duo X ( https://moddevices.com/product/mod-duo-x/ ) is another programmable, MIDI and audio capable module.

Thanks @Dragos. It seems like you have considered this before I posted my question. Your input is valued.

Just an aside from this topic, I have noticed, scouring the web, that interest for "Physical Hardware" external Synth or VST control (not just for DAW) is stirring.

Maybe a bubble burst from the "dive-in-head-first" adoption of "cheaper" Synth VSTs.

But add to this the unforseen adoption of constant Driver downloads, OS updates, compatability issues, fudges, bugs, patches, more bugs, obscure deep dive parameter anomalies, troubleshooting, internet outages, unexpected high $$ obsoletion expenses , user/ password/licence/subscription management....

It's a wonder VST Synth users have time to make any music at all.

And it makes the whole VST music world inaccessible to all except the most IT Savvy or hardy musicians.

Even so, I can't help feeling that the "IT Gurus, turned musical hobbyists" are missing out on the experience of having a "gnarly, warty" instrument in their hands, that responds immediately to fleshy touches.

For example, although electronic, The MiniMoog was "played" real time, live, on Arena stages, with as much finesse, angst, and weep inducing power as any violin, guitar, piano, sax... but it did have at least a few piano keys and many knobs. Not a Touchscreen GUI.

Can you really improvise on a Mouse click or make an audience weep with an iPad touchscreen Swipe?

Hope Yamaha is listening. They probably are. I used to work for NEC... lol.

If there is a money making market for Hardware parameter control of VST Synths (and I don't mean Mod Wheels, Pitch Bend, Volume etc), hopefully Yamaha will throw it into their R&D.

Thanks @Dragos. It seems like you have considered this before I posted my question.

I kind of did, but just in passing.

I am thinking of getting a Mixface SL anyway, for various purposes, so it would be obvious to try to use it thru Loomer Architect to augment the number of controls for the MODX, if that would be doable without a lot of effort.

I'm also quite interested in the Mod Devices' stuff, since it's so customisable and programmable (and has MIDI). It started as a kind of "ultimate guitar pedal thing" and evolved into a "wonder box of everything" (check this fun video to see it being an analog synthesizer: https://youtu.be/CFWWy3d5tww?t=683 ).
So yeah, obviously if one is having such devices available, a lot of thoughts will fly in various directions on what can be done with them.

But, TBH, I think the simple answer to your initial post might very well be "just get a Montage".
Not just because it gives you 8 sliders and 8 knobs, but it also gives you all that useful right side panel with tons of buttons for direct access to Parts, Elements, OPs etc. which in itself can speed the navigation.

I happen to like the UI and workflow of the MODX quite a lot (yes, it can be improved in lots of ways but I think it does the job nicely as it is), but the more I use it the more I have the impression I would like the Montage quite a bit more (I use buttons a lot, as opposed to the touch screen, even on the MODX).
I can't justify such a purchase as this is just a hobby, but it's pretty clear to me that the Montage gives you quicker access to everything in the engine.

If you do work a lot with the MODX connected to a computer, you should really try the John Melas Performance Editor, as it gives streamlined access to multiple parameters at once for FM-X patches (check this vid at 8:24 https://youtu.be/D2tjqQcgFN0?t=504 ).

Is there a publicly available list of EVERYTHING of the MODX that can be externally controlled?

And does it have useful things like ranges for parameters and anything much else useful to determining the degree to which external controllers can assist in better operation of the internals?

The Data List Manual starting around Page 185. Further down you'll see all the required SysEx formats, and then all the MIDI Prameter Change Tables. It looks like everything can be changed with SysEx.

Can you see how to change the values of time and amount for each of the ADDR values in Elements and Operators?

I can't.

I'd imagine it's gotta be a triple message: Identity of Part(1 through 16), Identity of Element/Operator (1 thru 8) and then the key (ADDR of Filter or Amplitude) and a value for either the time or property.

In a positive, it looks like an external, custom controller can dynamically adjust the Velocity and Gate of running arpeggios, something that the SuperKnob and Assignables cannot.

Using the following data list because it showed up first in a search:
https://usa.yamaha.com/files/download/other_assets/2/1192592/modx_en_dl_d0.pdf

Page 220 under "MIDI Parameter Change Table (FM Part Operator)"

You'll notice the address middle byte shows "op" where the upper nibble is represented by the variable "o" meaning operator number and lower nibble is represented by the variable "p" meaning part number. Therefore, there is no need to send multiple messages to identify this or that - the registers are arranged in a way such that different addresses reach different parts and different operators.

If you wanted to reach operator 1 of part 1 then "op" would be "00". If you wanted to reach operator 8 of part 5 then the "op" value would be "74" (in hex - which is 116 in decimal.

Address high, middle, low and other concepts covered here: https://www.yamahasynth.com/ask-a-question/how-to-send-sysex-commands-to-modx

You'll notice this area of the spec has the AEG registers for operators.

The layout and documentation is fairly good.

Address high, middle, low and other concepts covered here: https://www.yamahasynth.com/ask-a-question/how-to-send-sysex-commands-to-modx

You'll notice this area of the spec has the AEG registers for operators.

The layout and documentation is fairly good.

So good it required you to write huge screeds to explain it.

You didn't exactly apply yourself very much when directed to the data list. Therefore, more spoon-feeding was necessary. I find very little lacking the documentation. It outlines the commands to change parameters - explains what most all of the bytes do - has tables with ranges and default values organized in a reasonable way.

The most major of gripe I've had on this part of the documentation is calculation of the checksum. The algorithm is incorrect. Not difficult to arrive at the correct algorithm by doing a dump and seeing the checksums the hardware creates then working out the corrected algorithm.

Otherwise, the docs are OK.