I have my Motif XF connected via USB-MIDI (USB to host) to my PC. I also have 1/4 TS cabling from the Motif's stereo outputs connected to an audio interface, which is in turn connected via another USB cable to my PC as well. I've installed the Motif XF Editor, and set up Cubase AI 6 for the Motif. Everything works fine. But I'm super curious about how the Motif VST is wired behind the scenes...
Two channels show up in the VST folder. One of them just appears to be a standard audio channel that the VST outputs a stereo signal to. These signals can be routed inside the VST itself, and with FireWire you can have 16 of these channels all playing at once. That part seems self-explanatory, but what is the second channel I see? What does it do? It doesn't appear to do anything, and it's just labelled something like: "Motif XF VST". I never see any signal come out of it.
To my understanding, Cubase routes the signals as follows when set up correctly:
A MIDI track in Cubase (out) >> (in) Motif XF Editor VST (out) >> (in) Motif XF internal tone generator (out) >> (in) Motif XF Editor VST (out) >> (in) Configured stereo output (out) >> (in) Speakers
In Cubase, when I select a MIDI channel, I can assign it's output to the Motif XF VST. Then everything works as expected. But I also noticed that I can assign it's output directly to the Motif XF through the USB-MIDI port 1. In other words, I can skip routing to the VST in the second step above, and route straight to the Motif XF internal tone generator. I believe I get the exact same result, but I'm not totally sure. I mean, I can still use the XF Editor. I can still modify the parameters in real time with the mouse. I can still hear the same sound, and all insert effects on the XF VST audio channel remain the same. They don't disappear as I would expect.
In which case I begin to question... what is the point of routing to the XF Editor VST in the second step above? What are the advantages? Do I miss out on anything if I skip it? Isn't it faster to skip it because there's less rerouting?
Final bits of curiosity:
What is the USB-MIDI port 4 used for? In the Motif XF Owner's Manual it states that it's used for XF specific communications. Is it used for bulk transfers? Does it contain data regarding the output of the XF Editor and the XF itself?
I notice that when I set up the XF Editor and everything is all synchronized and ready, that my default audio output channels (Stereo outputs on my audio interface) get "disconnected". This is according to the VST Connections menu in Cubase. However I know this cannot be literally true under the hood, since I can still hear audio from the corresponding speakers, and is probably done by the XF Editor to hide certain information or something. Why?
It's a lot of questions I know... Thanks in advance for trying to answer even one of them. I know some of the questions are pretty technical and relevant to Cubase AI 6 in particular. But I can't think of anywhere else to post this except maybe the Steinberg forums. Even then, it would probably be considered too specific to the hardware involved. That is, the XF.