Having had an opportunity to test Marantz SR5015 vs Onkyo TX-RZ70, 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 - 7.2 versus 11.2, respectively, for devices. In terms of power, there are differences, the SR5015 has such a ratio W/Ohm - 100/8, 200/6, while the TX-RZ70 has a power of 140/8. A common feature for devices is the same total harmonic distortion - 0.08%. Each of the compared opponents supports Bi-amping. Both Marantz SR5015 and Onkyo TX-RZ70 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 Marantz SR5015 works with Deezer, TIDAL, Pandora, SiriusXM, Napster, SoundCloud, but the Onkyo TX-RZ70 works with Deezer, TIDAL, Pandora, SiriusXM, Napster, SoundCloud, Amazon Music, Amazon Music HD, MOOD:Mix.
The HDR10+ function is present in each of the rivals. The quality of 4K/120Hz 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 SR5015 and the TX-RZ70. 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 SR5015 has 6/2, and the TX-RZ70 has 7/3. HDMI Audio Return Channel is implemented in both devices. HDMI eARC is supported by the SR5015 and the TX-RZ70. When comparing receivers, it becomes clear that each of the rivals can work with HDMI CEC. SR5015 and TX-RZ70 support the standard HDCP 2.3. In the presence of a built-in phono stage for connecting a vinyl player only at Marantz SR5015.
Unlike the SR5015 where 2 Multi zones is provided, the TX-RZ70 works with 3 Multi zones. Voice control is performed using Amazon Alexa, Google Assistant, Siri, Josh.AI in both models. There is an ECO mode in either AV receiver. The Marantz SR5015 and the Onkyo TX-RZ70 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.