It makes sense comparing Onkyo TX-NR555 vs Sony STRZA5000ES because they both are able to give some premium features.
A significant difference between the receivers in the number of channels, Onkyo TX-NR555 has 7.2 versus 9.2 for Sony STRZA5000ES. Regarding power, then TX-NR555 has such a W/Ohm ratio - 130/6 when STRZA5000ES has a power of 130/8. The THD is 0.08% for the TX-NR555 but 0.09% for the STRZA5000ES. Both the TX-NR555 and the STRZA5000ES support Bi-amping. Each of the AV receivers can transmit an audio signal directly to the amplifier and bypasses any DSP processing. Only the TX-NR555 has Bluetooth support. Only the TX-NR555 supports Spotify. 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 STRZA5000ES can scale the input HDMI signal, unlike the TX-NR555. Dolby Vision technology found support only on the STRZA5000ES.
The Onkyo TX-NR555 has 6/1 HDMI inputs/outputs versus 6/2 HDMI connectors of the Sony STRZA5000ES. The HDMI Audio Return Channel (ARC) feature supports both devices. Unfortunately, HDMI eARC is not available on monitored devices. 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-NR555 has a built-in phono stage for connecting a vinyl player.
The TX-NR555 supports 2 Multi-room zones, versus 3 for the STRZA5000ES. A voice control is not available. An ECO mode is only available for the TX-NR555. The setup assistant will help you configure Sony STRZA5000ES.
Both devices have support for Dolby Atmos multichannel audio format. The surround sound technology DTS:X is supported by devices under review.