It makes sense comparing Marantz SR6010 vs Onkyo TX-8020 because they both are able to give some premium features.
A significant difference between the receivers in the number of channels, Marantz SR6010 has 7.2 versus 2.0 for Onkyo TX-8020. Regarding power, then SR6010 has such a W/Ohm ratio - 110/8, 150/6 when TX-8020 has a power of 90/6. The THD is 0.05% for the SR6010 but 0.03% for the TX-8020.
Characteristics of digital to analog converter (DAC) are different, 192 KHz/32-bit for SR6010 and 192 KHz/24-bit for the TX-8020. Only the SR6010 supports Bi-amping feature. Each of the AV receivers can transmit an audio signal directly to the amplifier and bypasses any DSP processing.
Only the Marantz SR6010 can connect to the Internet via WI-FI. Only the SR6010 has Bluetooth support. The Apple Music service is implemented on considered devices: AirPlay. Only the SR6010 supports Spotify.
Only the Marantz SR6010 has support for High dynamic range (HDR). Only the SR6010 provides HDMI signal transmission in standby mode. The SR6010 can scale the input HDMI signal, unlike the TX-8020. The HDR standard - Dolby Vision is not supported by these receivers. Only the SR6010 supports HDMI Audio Return Channel (ARC). Unfortunately, HDMI eARC is not available on monitored devices. Of the two receivers in our comparison, HDMI CEC is present in only the SR6010. These compared receivers have a built-in phono stage for connecting a vinyl player. A voice control is not available. An ECO mode is only available for the SR6010. The setup assistant will help you configure Marantz SR6010.
Only the SR6010 has a Dolby Atmos multichannel audio format support. A surround technology DTS:X is supported only by the SR6010.
The Marantz SR6010 is better receiver in this comparison. Check Marantz SR6010 price