I'm trying to gain a better understanding on how MIDI is implemented on the USB connectors of ARP. Throughout the manual, mention is made of MIDI data flowing into/out of 5-pin DIN or USB - with no differentiation of either USB-A or USB-B connectors. Only on page 22 I see:
"USB
The Type-B USB port provides power to the unit. It also supports MIDI over USB to connect
to software sound generators, VSTs and DAWs.
It supports both incoming and outgoing MIDI clock and MIDI note messages.
USB Host
The Type-A USB Host port support MIDI note and CC input from a USB MIDI device such as
a keyboard or sequence. "
Paraphrasing, USB-B has MIDI data in and out, and USB-A has MIDI data in only. This is not my experience, and I'm wondering if I am doing something wrong.
I put a MIDI controller on the USB-A connector and it spits out MIDI notes for the ARP to listen to and generate its own MIDI notes. ARP sends its MIDI note data out the USB-B connector which is then sounded by my synths. So far, so good. The problem I'm running into is that ARP appears to be also sending MIDI note data that it generates out the USB-A port as well. Since my controller is on the USB-A port, it receives the ARP MIDI data and passes it back to its output, which is the USB-A port. With the ARP set to MIDI THRU mode, the net result is to have double MIDI traffic on the USB-B port.
As an example, ARP sends out a MIDI On command on USB-B, and it would appear on USB-A as well. This MIDI On command is returned to the MIDI-A connector via the controller. This same MIDI On command comes out the USB-B connector again. Same scenario happens with MIDI Off commands.
I would appreciate it if the behaviour mirrored the description in the manual, such that USB-A supports MIDI note and CC input from a controller and does not send MIDI out from the ARP on the USB-A connector. Is this possible?
Only reason I ask this is because I've run out of USB Host connectors on my router, and I would like to essentially daisy chain the ARP in between the router and controller. Otherwise, something else will have to go in order to make room for ARP.
Thanks, and hope this makes sense. And, if I've got anything set up incorrectly, please let me know.
P.S. BTW, the manual makes no mention of USB-A accepting MIDI clock and Start/Stop controls. I've found it responds to those as well. This I would need to be in place, so I appreciate it does not fully follow the manual in this instance.
Thank you for the reply and clarification. Seems it works as intended. Unfortunately, I cannot disable MIDI Thru on the external controller. Alas it appears that my plan of daisy chaining will not work. Something else will have to give up a place on the limited and coveted MIDI IN slots on my router.
At any rate, as a request, could a future software version supply a switch for enabling/disabling MIDI Out data on the USB-A host connector? Perhaps on the Menu button of the Set Mode. I do see the benefit of putting MIDI Out data on the USB-A, for this allows, say, a portable setup to consist of just the ARP and an external synth.