Onkyo TX-SR501 6.1-Channel Home Theater Receiver Product Information The Fully-Equipped 6.1-Channel Receiver for Your Entry Into the World of Home Theater. Onkyo has redefined how you will forever look at an entry-level home theater receiver with the TX-SR501. Those new to home theater will breathe a sigh of relief due to the user-friendly design that incorporates color-coded inputs and outputs, a logically laid-out front panel and an easy-to-use remote control.