I have used up all 6 inputs on the IRF-6. I have a least one piece of equipment, my subwoofer that I want to add to the IRF-6. The sub is not near the equipment rack that is why I cannot use one of the double emiters. My quesion is which deviced do I need to expand the ports? Can I use a Xantech expansion block or do I need a connecting block with another power supply? If I only need to add one IR maybe I can use a Y adapter. Specific recommendations would be appreciated. Thank you.