I received my Arc today. After unboxing, I updated an old patch I had lying around to be controlled by it. The patch mimics a long-wave radio, and the "stations" I tune into are soundfiles lying on my desktop. It was actually originally made to be controlled by the Griffin Powermate knob. But this upgrade to Arc gives me much better control through high resolution and visual feedback. One knob is for tuning in larger/coarser steps and the other for fine tuning into the stations spread around the Arc.