If I understand what I've read about the 612, it's a dual-tuner single-output receiver (and should be called a 621 IMHO). Anyhow, you don't say what you have on your antenna in the way of legacy or dish pro or dish pro plus switches and LNBs. If you already have a DPP44 or otherwise a DPP switch integrated inside your feedhorn assembly, then you're good to go with exactly the same number of cables you have now. You just split the cable at your receiver with the separator that comes with dual-tuner receivers.