Yeah, of course you can use your computer/daw if you have a midi interface or audio interface with built in midi interface. Your computer is an usb host.
You just route the controller through a midi track in your daw, set midi output to the AR (the midi output your AR is connected to). Send on the midi channel that is selected for performance in the AR (project menu -> midi -> channels -> scroll down to performance.
Do you have all that? Which daw do you use?
Or you can connect A4 to AR and make sure both have performance set to the same midi channel.
Also make sure the knobs are set up to output CC (also project menu -> midi).