Yamaha RX-V585BL vs Yamaha RX-V4A comparison definitely makes sense.
A significant difference between the receivers in the number of channels, Yamaha RX-V585BL has 7.2 versus 5.2 for Yamaha RX-V4A. Regarding power, then RX-V585BL has such a W/Ohm ratio - 80/8, 145/6 when RX-V4A has a power of 80/6. The THD is 0.09% for the RX-V585BL but 0.06% for the RX-V4A. Both the RX-V585BL and the RX-V4A support Bi-amping. Each of the AV receivers can transmit an audio signal directly to the amplifier and bypasses any DSP processing.
WI-FI modules have the same characteristics: 2.4/5GHz. Rivals from our review have Bluetooth support. The Apple Music service is implemented on considered devices: AirPlay, AirPlay 2. Spotify can be used on each receiver. The RX-V585BL can work with the audio stream from Deezer, TIDAL, Pandora, Napster, SiriusXM, TuneIn Radio, and the RX-V4A can receive a content from Deezer, TIDAL, Pandora, SiriusXM, Qobuz.
Both AV receivers support HDR10 technology (High dynamic range). HDMI signal transmission in standby mode is implemented in each of the devices. Both rivals can scale the resolution of the incoming HDMI signal. The HDR standard - Dolby Vision is supported by these receivers.
Each receiver has 4/1 HDMI inputs/outputs. The HDMI Audio Return Channel (ARC) feature supports both devices. HDMI eARC is available in each model. The Consumer Electronics Control (CEC) feature is present in most modern AV receivers and the models in our comparison are no exception. The RX-V585BL supports the protection of digital content of the standard HDCP 2.2, versus HDCP 2.3 in the RX-V4A. Receivers do not have a built-in phono stage for connecting a vinyl player. Supported voice control technologies are identical - Amazon Alexa, Google Assistant, Siri. It is also worth noting that the ECO mode is presented in each of the receivers. Both RX-V585BL and RX-V4A can be configured using the Setup assistant.
Only the RX-V585BL has a Dolby Atmos multichannel audio format support. A surround technology DTS:X is supported only by the RX-V585BL.