So I have an HD 500 that I use live and a marshall half stack for home use. I want to get into some home studio recording and I need a Digital Audio interface to record the way I want to. What I want to know, before I go out and buy a microphone, is can I use the mic input on my HD 500 as a digital audio interface to record my Marshall Half stack? The HD 500 has a USB out that I have recorded into Garageband lots on its own but can you record the mic input into garageband???