When routing to a MIDI Instrument (rather than a VST Instrument) I basically find that applying any Expression Map kills (distorts) the Midi output. Is this a known issue or should I troubleshoot further at my end…?
I’ve had mixed results, but I did not troubleshooting systematically either… Sometimes it was fine, sometimes it wasn’t.
I have had mixed results, including what seem to be distortions (or some other control signal unexpectedly being sent), but I have chalked it up my own difficulties in getting polished expression maps to behave as expected. I’ve pretty much put aside Dorico’s playback for my orchestral works until Noteperformer lands on shores of Steinberg-land. (I’m sure it’s doable, I just lack the time for experimentation.)
What happens here is basically that if the output is set to a Midi channel for which no Expression map is configured, the NOTE data are transmitted correctly. As soon as an Expression Map is configured for that channel, all note data are folded to C0, while the CC data (from the Xmap) are transmitted correctly. So the problem is not the configuration of the Xmap itself, it’s the mere presence of it…
I think I was once able to get rid of this, but what I recall from it is so tremendously silly I almost feel weird suggesting it.
When you set the number of channels, even if you don’t change the amount, the expression maps will pop up, correct? (Without explicitly setting up the channels, you should just get MIDI through on all 16 by default.) Both the Expression Map and the Percussion Map columns, both filled in. Delete the text in the Percussion Map text field (or vice versa) and apply. Make it sure it stays empty — you might have to input a space instead of just deleting what’s there.
That’s it. I’ve just tried it again, to make sure memory wasn’t playing tricks, and it works. This was either a big oversight, or there’s a nasty bug in the way.
Thanks Luís, you are absolutely right! Entering a SPACE (left empty it just reverts back to GM) in the Percussion map column fixes the problem. (Both these columns should have a NONE setting I guess…? ) My tried and true virtual orchestra is living happily in a Cubase/VEP network, so now I will have another go at challenging it from Dorico tomorrow. Oversight or bug, a WarninG is at least in order 
Thanks.
Glad to know I was on the money, or rather that my experience was reproducible and not some odd behavior here, because you might understand how what I suggested might have sounded at first! It’s one of those cases where it’s so simple it just seems impossible to be true. As I said, either our friends left some loose ends, or some wires got crossed in the process.
I hope we get a native way to manage MIDI connections soon. I’ve been using Max to manually make sure there is no loopback. I’ve blacklisted only the virtual ports Max creates when it’s running, and I just send everything there. Haven’t bothered to setup a whole orchestra outside while Dorico is talking to the DAW because, as of yet, it still feels like a trudge.
And if we could get ReWire anytime soon, even if just to sync transports… italian hand kissing motion