It’s strongly recommended to compare different receivers if you want to choose the best one: Marantz NR1508 vs Onkyo TX-RZ720.
The number of channels for receivers is different - 5.2 versus 7.2, respectively, for devices. In terms of power, there are differences, the NR1508 has such a ratio W/Ohm - 50/8, while the TX-RZ720 has a power of 175/6. A common feature for devices is the same total harmonic distortion - 0.08%.
The manufacturer installed different DACs, the NR1508 received the model 192 KHz/24-bit, but the TX-RZ720 is equipped with VLSC 384 KHz/32-bit. The Bi-amping function is implemented only in the Onkyo TX-RZ720. Both Marantz NR1508 and Onkyo TX-RZ720 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. The contenders have differences in the supported services from Apple - AirPlay, AirPlay 2 versus AirPlay respectively. Access to the Spotify service is on each of the competitors. The number of available streaming services varies for receivers, the Marantz NR1508 works with Deezer, TIDAL, Pandora, but the Onkyo TX-RZ720 works with Deezer, TIDAL, TuneIn Radio. 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 NR1508 and the TX-RZ720. None 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 NR1508 has 6/1, and the TX-RZ720 has 7/2. HDMI Audio Return Channel is only available on Onkyo TX-RZ720. HDMI eARC is not supported by the NR1508 and the TX-RZ720. When comparing receivers, it becomes clear that each of the rivals can work with HDMI CEC. NR1508 and TX-RZ720 support the standard HDCP 2.2. In the presence of a built-in phono stage for connecting a vinyl player only at Onkyo TX-RZ720. There is an ECO mode in NR1508. The Marantz NR1508 and the Onkyo TX-RZ720 can be properly configured using the setup assistant.
A Dolby Atmos multichannel audio format is available only in the TX-RZ720. Only in the TX-RZ720 realized a DTS:X surround technology.