my PC has only one MIDI-IN. I have two keyboards and two virtual instruments loaded. Now I want to play virtual instrument #A with Keyboard #1 and virtual instrument #B with Keyboard #2 at the same time. I have a sound interface connected with two stereo outputs. So that I hear #A thru stereo output #1 and #B thru stereo output #2. Is that possible with only one MIDI-IN at the PC by using e.g. MIDI-THRU?
I don't think you can have 2 separte controllers in with only 1 midi input. you can control your 2 software synths with one controller, but I am not sure if you can do both at the same time with your set up. your midi in will see one device, on 16 channells, and out the same way. Maybe you can try some complex scheme like using midi out into one keyboard then thru with the other into your midi in, and trying to get the first keyboard to trigger just on midi 1, and your second just on midi 2, not sure how to do that now. I would think about spending like a hundred and fifty and getting a cheaper new midi interface with more in's and outs, really easy and should be recognized by your computer
1. Research if either of your keyboards can be configured to send it's midi in, out along with the midi signal that key board is generating. Some boards had the option to do that, applying the thru out on the midi out jack.
2. If either of your keyboards has a usb out and your computer has usb ins, use that for one of your solutions.