Onkyo Receivers, Audio Video Receiver, Surround Sound Receiver, AV ReceiverHome stereo receivers interpret the audio signal and power all of your speakers. 2-channel receivers are stereo receivers generally used for listening to music, and they often lack the HDMI and other inputs that an A/V receiver would include. 5.1 and 7.1-channel receivers are audio video receivers meant for surround sound systems. They will have multiple HDMI and audio inputs for switching between sources such as a cable box, streaming device, Blu-ray player, etc. Higher end receivers will have better digital audio converters for higher fidelity sound, and will have more robust power supplies to power larger speakers.