It makes sense comparing Yamaha RX-V671 vs Marantz SR7015 because they both are able to give some premium features.
A significant difference between the receivers in the number of channels, Yamaha RX-V671 has 7.1 versus 9.2 for Marantz SR7015. Regarding power, then RX-V671 has such a W/Ohm ratio - 90/8, 150/4 when SR7015 has a power of 125/8, 165/6. The THD is 0.09% for the RX-V671 but 0.05% for the SR7015. Both the RX-V671 and the SR7015 support Bi-amping. Each of the AV receivers can transmit an audio signal directly to the amplifier and bypasses any DSP processing. Rivals from our review have Bluetooth support. Only the SR7015 supports Spotify. The RX-V671 can work with the audio stream from Napster, and the SR7015 can receive a content from Deezer, TIDAL, Pandora, SiriusXM, Napster, SoundCloud. HDMI signal transmission in standby mode is implemented in each of the devices. Both rivals can scale the resolution of the incoming HDMI signal. Dolby Vision technology found support only on the SR7015.
The Yamaha RX-V671 has 6/1 HDMI inputs/outputs versus 8/3 HDMI connectors of the Marantz SR7015. The HDMI Audio Return Channel (ARC) feature supports both devices. The HDMI eARC is available only on the SR7015. The Consumer Electronics Control (CEC) feature is present in most modern AV receivers and the models in our comparison are no exception. The RX-V671 supports the protection of digital content of the standard HDCP 2.2, versus HDCP 2.3 in the SR7015. These compared receivers have a built-in phono stage for connecting a vinyl player.
The RX-V671 supports 2 Multi-room zones, versus 3 for the SR7015. An ECO mode is only available for the SR7015. The setup assistant will help you configure Marantz SR7015.
Only the SR7015 has a Dolby Atmos multichannel audio format support. A surround technology DTS:X is supported only by the SR7015.