So I've had a 2012 Macbook pro that ran Logic Pro 9 and used a USB cable from my Roland RD 700GX to record in Logic.
I also used an old MIDI to USB Cable to do the same with my Yamaha.
When I switched to my 2015 Macbook Pro that came with Sierra, I downloaded Logic Pro X. IU never got the Yamaha to work again and it took me a while to figure out how to use the Roland by downloading a driver.
Now I again bought a new laptop, The latest Macbook pro that came with High Sierra and now I'm unable to use any of my piano's as a MIDI controller.
Can someone please help me?