Can someone shed some light on the difference between "live mode" and cab bypass on the HD300 and 400. Is it the cab with mic models bypassed? I'd like to run the HD300 into my PC without cab simulation so I can use IR's in my DAW. I've heard the 500 will completely bypass the cab sounds and I'd just like to find a solid answer on weather or not this can be done on the other two units. Anyone?