I don’t have an M:S but I do have the M:C and I am going to presume that the settings are probably the same if not very similar.
You send program change messages from your M:S by setting your Out Chan >> to PCH Out 8 (you can choose a different midi channel if you like but don’t go for 1 or 2 as these channels are in use on the JX-08 for the 2 separate synth tracks / channel a=1 b=2 on the JX-08 and you can maybe use these channels to send note info from another device to play the JX-08)
On your JX press menu (no note /seq or start selected) - turn the value dial to Midi or choose key 3 and then you get into the midi settings.
A new set of led’s light up as another option menu.
key 1 = CH - press the value dial and turn it to select channel 8 (in this example using CH8 as program change out message channel on the M:C / M:S)
key 5 = Sync - press the value button and select midi
key 6 = Syn.0 - press the value button and select midi (maybe not necessary but I have it set like this)
Connect with midi dongle that you got with your M:S and cable out from M:S to regular midi in on JX-08.
Now when you select and start T1/1 on your M:S it will play the pattern you’ve created on your M:S but also play pattern P.A.11 in sync on your JX-08 as it’s being midi clocked and sent the program change value by your M:S.
So then you have Prg changes that are configured thus (first few examples)>
M:S JX-08
T1/1. P.A.11
T1/2. P.A.12
T1/3. P.A.13
etc
Play around with it and you’ll see how it works!
I haven’t played too much with the arp settings on the JX-08. I will have a play and let you know at some point but it seems pretty straightforward to me.
I really do love this synth and yeah I do understand your comment about the seq after using the Elektron seq but again… you just need a little time and it clicks really quickly. I am using mine with a keystep to input notes mostly because I prefer playing more intuitively to programming but it is ok to program too - just not as immediate.
… and one more thing if you haven’t got it yet… When you are playing back a pattern on the JX-08, if you select the synth sound by holding down the note button and pressing key 1 or 2 while in live record mode (hold note and press start) you can adjust any parameter on the panel and you are motion recording so you can (for the simplest example) adjust cutoff freq to sweep into a brighter sound. This makes this synth mega powerful and a hell of a lot of fun to use.