Yamaha RX-A780 vs Onkyo TX-RZ840 comparison definitely makes sense.
A significant difference between the receivers in the number of channels, Yamaha RX-A780 has 7.2 versus 9.2 for Onkyo TX-RZ840. Regarding power, then RX-A780 has such a W/Ohm ratio - 95/8, 160/4 when TX-RZ840 has a power of 180/6. The THD is 0.06% for the RX-A780 but 0.08% for the TX-RZ840.
Characteristics of digital to analog converter (DAC) are different, Burr-Brown 384 KHz/32-bit for RX-A780 and AKM 384 KHz/32-bit for the TX-RZ840. Both the RX-A780 and the TX-RZ840 support Bi-amping. 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 Apple Music service is implemented on considered devices: AirPlay, AirPlay 2. Spotify can be used on each receiver. The RX-A780 can work with the audio stream from Deezer, TIDAL, Pandora, Napster, SiriusXM, Qobuz, and the TX-RZ840 can receive a content from Deezer, TIDAL, Pandora, TuneIn Radio.
Both AV receivers support HDR10 technology (High dynamic range). 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 RX-A780 can scale the input HDMI signal, unlike the TX-RZ840. The HDR standard - Dolby Vision is supported by these receivers.
Each receiver has 7/2 HDMI inputs/outputs. The HDMI Audio Return Channel (ARC) feature supports both devices. HDMI eARC is available in each model. The Consumer Electronics Control (CEC) feature is present in most modern AV receivers and the models in our comparison are no exception. The RX-A780 supports the protection of digital content of the standard HDCP 2.3, versus HDCP 2.2 in the TX-RZ840. These compared receivers have a built-in phono stage for connecting a vinyl player.
The RX-A780 supports 2 Multi-room zones, versus 3 for the TX-RZ840. The RX-A780 supports voice control via Amazon Alexa, Google Assistant, and the TX-RZ840 - Google Assistant. An ECO mode is only available for the RX-A780. Both RX-A780 and TX-RZ840 can be configured using the Setup assistant.
Both devices have support for Dolby Atmos multichannel audio format. The surround sound technology DTS:X is supported by devices under review.