Having had an opportunity to test Onkyo TX-RZ920 vs Pioneer Elite SC-LX904, I’d like to share my impression here to facilitate your choice of a new AV receiver.
The number of channels for receivers is different - 9.2 versus 11.2, respectively, for devices. In terms of power, there are differences, the TX-RZ920 has such a ratio W/Ohm - 135/8, 175/6, while the Elite SC-LX904 has a power of 140/8. The value of total harmonic distortion is also different, and for the TX-RZ920 it is 0.04%, but for the Elite SC-LX904 it is 0.08%.
The manufacturer installed different DACs, the TX-RZ920 received the model AK4490 384 KHz/32-bit, but the Elite SC-LX904 is equipped with ES9026PRO 384 KHz/32-bit. Each of the compared opponents supports Bi-amping. Both Onkyo TX-RZ920 and Pioneer Elite SC-LX904 can transmit an audio signal directly to the amplifier and bypasses any DSP processing.
These units have the same Wi-Fi modules. Each of the receivers has a Bluetooth connector. Both devices can work with such Apple Music services: AirPlay, AirPlay 2. Access to the Spotify service is on each of the competitors. The number of available streaming services varies for receivers, the Onkyo TX-RZ920 works with Deezer, TIDAL, Pandora, TuneIn Radio, but the Pioneer Elite SC-LX904 works with Deezer, TIDAL, Pandora.
The HDR10 function is present in each of the rivals. The quality of 4K/60Hz signal remains unchanged when transmitting from a source to a TV or projector via HDMI for both receivers. Signaling over HDMI in standby mode can provide the TX-RZ920 and the Elite SC-LX904. Each of the devices can increase the resolution of the incoming video signal. Each of the participants of the comparison has a Dolby Vision.
The number of HDMI inputs/outputs varies depending on the receiver, the TX-RZ920 has 8/2, and the Elite SC-LX904 has 7/3. HDMI Audio Return Channel is implemented in both devices. HDMI eARC is supported by the TX-RZ920 and the Elite SC-LX904. When comparing receivers, it becomes clear that each of the rivals can work with HDMI CEC. The TX-RZ920 has support for the standard HDCP 2.2, compared to the Elite SC-LX904, which supports the standard HDCP 2.3. Like most receivers, our models have a built-in phono stage for connecting a vinyl player.
Ability to create 3 Multi zones inherent in both AV receivers. For voice control in the TX-RZ920 is used Google Assistant, but in the Elite SC-LX904 is used Amazon Alexa. There is an ECO mode in neither AV receiver. The Onkyo TX-RZ920 and the Pioneer Elite SC-LX904 can be properly configured using the setup assistant.
A Dolby Atmos multichannel audio format is available both models. A DTS:X surround technology is supported by devices from our comparison.