This is likely to work similar to your Motif XF8 experience:

Start with a PERFORMANCE that has a PART filled in to position 9-16. You can just take your current PERFORMANCE you're working with to start the "patch change" trick. Take that PERFORMANCE and:

1) Press button [PERFORMANCE] (HOME)
2) Hold the [SHIFT] button while pressing [PERFORMANCE CONTROL] - this will bring up PARTs 9-16
3) Touchscreen (TS): Press the [+] to add a part
4) Select any preset part you choose. You can set the level to 0 for this part since it's just there to turn off SSS (the sustain feature = issue for your use)
5) Press [STORE] to save the new PERFORMANCE.

Now take a listen at how the notes no longer sustain when you change to another PERFORMANCE coming from this modified one.

Can this be done via MIDI signals?

L. Spiro

Yes, save the performance then MSB/LSB+PC switch.

One stored, your user performance will have an MSB/LSB+PC address. To find those stats, press PERFORMANCE (HOME), then use the touchscreen to touch the PERFORMANCE name. A popup will show up with the bottom option (left-hand side menu) as "Property". Touch "Property" and you'll see the current performance MSB/LSB (bank) + PC.

If doing via MIDI, wouldn't it be easiest to send an all notes off?

But to be honest, I don't understanding what you try to achieve. There should be easier ways to do it. Can you explain what you are trying to achieve, maybe we could help you finding something more straightforward.

I tried MIDI CC 120 (all sound off) and 123 (all notes off) as I mentioned; the device does not seem to respond to these, at least not how I expect. It needs to turn off all trailing reverb and effects, which it does not.

What I am trying to do:
In order to avoid polyphony issues when recording piano solos I record (in some cases) a single octave at a time.
I layer the recorded waveforms to get the final product. This is an example of the final product done this way: https://soundcloud.com/l-spiro/liebestraume
The sections with long sustains would have obvious note drop-off if recorded in a single take.

In order to align the waveforms perfectly it is necessary to have a dummy note at the start of each track.
By removing all empty silence prior to the dummy note, each track will be aligned so that layering will be completely indistinguishable from a single recording of a single track. Every octave in the recording above was done as a separate recording. Using my method, it is impossible to hear any misalignment between notes going between octaves etc.

Once the tracks are aligned, I merge them and remove the dummy note, then remove all the following silence until 0.5 seconds before the first note in the song.

This means that following the dummy note it must go back to literal silence again before the actual song begins.

The method proposed by Jason will not really solve the issue. I don’t need the note itself to stop; I already just tap the note and it stops immediately after. I need all sound to stop. Reverb is the primary problem here.
Reverb and effects continue for seconds after having already released the note, and while I can push the song 7 bars back after the dummy note to be sure that all sound has died off naturally, this is a serious waste of time when recording 10-minute songs split over 8 layered recordings.

L. Spiro

Okay, got it. Sounds very nice, btw.

What about the following (I am assuming you want single midi mode): Make a performance with not only the piano sound, but some other additional sound, the one you want to use for the synchronization. Split the keyboard so that that one sounds only on the highest or lowest key (which are probably not available from the keyboard, anyway). The piano should not sound there. Make sure the sync sound has no reverb or something, make a short release. Then you play it the sync key and then the normal piano and do not have to switch any program.

On the other hand in Jason's method, if you use parts 9-16 it *will* cutoff all reverb, actually. By what Jason proposed you switch the SSS off and then it behaves like the Motif in that aspect.

Hope that helps!

Hopefully, this may help sort out the behavior of "all notes off". The data list is by "go to" guide for Montage MIDI implementation. It has the SysEx commands documented, control change messages, etc. It's nicely done and has most items documented.

Interested in your experience with "all notes off" - I pulled up the doc ("montage_en_dl_v110_b0.pdf") and searched for "all notes".

Page 176 has a search "hit":

(3-2-3) ALL NOTE OFF (CONTROL NUMBER = 7BH, DATA VALUE = 0)
All the notes currently set to on in certain channel(s) are muted when receiving this message.
However, if Sustain or Sostenuto is on, notes will continue sounding until these are turned off.

Perhaps either Sustain or Sostenuto is causing the notes not to turn off (for CC 123)?

To "get around" this - perhaps you could precede the CC_123_data_value_0 with a CC_121_data_value_0. The CC 121 is supposed to turn off sustain and sustenuto - so one would think it would mute all notes.

... now CC 120 is supposed to mute everything. I didn't see any details listed here which limited the scope of when this works.

(3-2-1) ALL SOUND OFF (CONTROL NUMBER = 78H, DATA VALUE = 0)
All the sounds currently played including the Channel Messages such as Note-On and Hold-On in a certain
channel are muted when receiving this message.

... now taking a step back at the page 174 summary - I notice that CC 120, 121, 123 are channel mode messages and there's this information "(Seq only)". I'm wondering if that means only the recorder responds to these (Sequencer = Recorder). It's not documented anywhere what this means.

When you look at page 208 - you see the synthesizer (tone generator under MIDI / keyboard control) shows an "X" by "All Sound Off", "All Notes Off", and "Reset All Cntrls" - the three CC #s discussed here - but only for transmitted. Received for these three shows an "O" - so looks like they are received.

There is a little ambiguity between the "seq only" and "O" (supported) in receive. I've been holding off on responding because I wanted to test on my Montage - but I had a performance so it's not currently in the studio for me to try these.

Perhaps Yamaha can comment on the implications of when the specification shows "Seq Only" or "All In Seq" as I see these in multiple Yamaha specs but have not yet been able to find the documentation.

For now, I believe emulating the Motif program change behavior by forcing SSS off (previous instructions given) is the way to go. The above comments are aimed at advancing an understanding around the "all notes off" MIDI message. It's still a fair open question of how to properly utilize this MIDI message and what the limitations are.