It makes sense comparing Denon AVR-X8500HSP vs Yamaha RX-V671 because they both are able to give some premium features.
A significant difference between the receivers in the number of channels, Denon AVR-X8500HSP has 13.2 versus 7.1 for Yamaha RX-V671. Regarding power, then AVR-X8500HSP has such a W/Ohm ratio - 150/8, 190/6 when RX-V671 has a power of 90/8, 150/4. The THD is 0.05% for the AVR-X8500HSP but 0.09% for the RX-V671.
Characteristics of digital to analog converter (DAC) are different, AK4490 384 KHz/32-bit for AVR-X8500HSP and Burr-Brown 192 KHz/24-bit for the RX-V671. Both the AVR-X8500HSP and the RX-V671 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 AVR-X8500HSP supports Spotify. The AVR-X8500HSP can work with the audio stream from Deezer, TIDAL, Pandora, Napster, SiriusXM, TuneIn Radio, iHeart Radio, Sound Cloud, and the RX-V671 can receive a content from Napster.
Only the Denon AVR-X8500HSP has support for High dynamic range (HDR). Compared AV receivers retain the quality of 4K/60Hz signal when transmitting from a source to a TV or projector. 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 AVR-X8500HSP.
The Denon AVR-X8500HSP has 8/3 HDMI inputs/outputs versus 6/1 HDMI connectors of the Yamaha RX-V671. The HDMI Audio Return Channel (ARC) feature supports both devices. The HDMI eARC is available only on the AVR-X8500HSP. The Consumer Electronics Control (CEC) feature is present in most modern AV receivers and the models in our comparison are no exception. Both models support the standard HDCP 2.2. These compared receivers have a built-in phono stage for connecting a vinyl player.
The AVR-X8500HSP supports 3 Multi-room zones, versus 2 for the RX-V671. An ECO mode is only available for the AVR-X8500HSP. The setup assistant will help you configure Denon AVR-X8500HSP.
Only the AVR-X8500HSP has a Dolby Atmos multichannel audio format support. A surround technology DTS:X is supported only by the AVR-X8500HSP.