I contacted both Hercules and Klipsch. Neither could give me a method of getting the 6 channels of the GTXP to connect to the Promedia 5.1s. The tech recommended the Kenwood HTB-504 5.1 A/V receiver. It has 6 channel DVD inputs that connected to the GTXP without any problems. The HTB-504 was about the same price as the Promedia 5.1s.