Justin:
The Onkyo 474/484/494 are all latter day descendants of the 434. The 555 was in vogue when the 434 was, so it probably is AC-3 and not 5.1. Onkyo USA is located in Ramsey, New Jersey. You can probably call them and ask for information. (If you live in NY or NJ, Shortline buses go right by Onkyo.) Also, the existence of an A/B switch on a HT receiver, does not guarantee that you can run them both at the same time. Research that as well as model numbers. Good luck.
The Onkyo 474/484/494 are all latter day descendants of the 434. The 555 was in vogue when the 434 was, so it probably is AC-3 and not 5.1. Onkyo USA is located in Ramsey, New Jersey. You can probably call them and ask for information. (If you live in NY or NJ, Shortline buses go right by Onkyo.) Also, the existence of an A/B switch on a HT receiver, does not guarantee that you can run them both at the same time. Research that as well as model numbers. Good luck.