An affordable AV receiver is always a good option to consider, so Onkyo TX-RZ920 vs Yamaha RX-V475 comparison definitely makes sense.
A significant difference between the receivers in the number of channels, Onkyo TX-RZ920 has 9.2 versus 5.1 for Yamaha RX-V475. Regarding power, then TX-RZ920 has such a W/Ohm ratio - 135/8, 175/6 when RX-V475 has a power of 80/6. The THD is 0.04% for the TX-RZ920 but 0.09% for the RX-V475.
Characteristics of digital to analog converter (DAC) are different, AK4490 384 KHz/32-bit for TX-RZ920 and Burr-Brown 192 KHz/24-bit for the RX-V475. Only the TX-RZ920 supports Bi-amping feature. Each of the AV receivers can transmit an audio signal directly to the amplifier and bypasses any DSP processing. Rivals from our review have Bluetooth support. The Onkyo TX-RZ920 has support for AirPlay, AirPlay 2, and its competitor in our comparison - AirPlay. Spotify can be used on each receiver. Compared AV receivers retain the quality of 4K/60Hz signal when transmitting from a source to a TV or projector. HDMI signal transmission in standby mode is implemented in each of the devices. The TX-RZ920 can scale the input HDMI signal, unlike the RX-V475. Dolby Vision technology found support only on the TX-RZ920.
The Onkyo TX-RZ920 has 8/2 HDMI inputs/outputs versus 5/1 HDMI connectors of the Yamaha RX-V475. The HDMI Audio Return Channel (ARC) feature supports both devices. The HDMI eARC is available only on the TX-RZ920. The Consumer Electronics Control (CEC) feature is present in most modern AV receivers and the models in our comparison are no exception. Both models support the standard HDCP 2.2. The TX-RZ920 has a built-in phono stage for connecting a vinyl player. An ECO mode is only available for the RX-V475. The setup assistant will help you configure Onkyo TX-RZ920.
Only the TX-RZ920 has a Dolby Atmos multichannel audio format support. A surround technology DTS:X is supported only by the TX-RZ920.