It makes sense comparing Yamaha RX-V581 vs Yamaha RX-V485 because they both are able to give some premium features.
A significant difference between the receivers in the number of channels, Yamaha RX-V581 has 7.2 versus 5.1 for Yamaha RX-V485. Regarding power, then RX-V581 has such a W/Ohm ratio - 115/6 when RX-V485 has a power of 80/8, 145/6. The THD is the same and is 0.09%.
Characteristics of digital to analog converter (DAC) are different, Burr-Brown 192 KHz/24-bit for RX-V581 and Burr-Brown 384 KHz/32-bit for the RX-V485. Both the RX-V581 and the RX-V485 support Bi-amping. Each of the AV receivers can transmit an audio signal directly to the amplifier and bypasses any DSP processing.
Both models have the ability to connect to the Internet via WI-FI. Rivals from our review have Bluetooth support. The Yamaha RX-V581 has support for AirPlay, and its competitor in our comparison - AirPlay, AirPlay 2. Spotify can be used on each receiver. The RX-V581 can work with the audio stream from Pandora, JUKE, and the RX-V485 can receive a content from Deezer, TIDAL, Pandora, Napster, SiriusXM. 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. The RX-V485 can scale the input HDMI signal, unlike the RX-V581. Dolby Vision technology found support only on the RX-V485.
Each receiver has 4/1 HDMI inputs/outputs. The HDMI Audio Return Channel (ARC) feature supports both devices. The HDMI eARC is available only on the RX-V485. The Consumer Electronics Control (CEC) feature is present in most modern AV receivers and the models in our comparison are no exception. The RX-V581 supports the protection of digital content of the standard HDCP 2.2, versus HDCP 2.3 in the RX-V485. Receivers do not have a built-in phono stage for connecting a vinyl player.
Each of the AV receivers from our review supports 2 Multi-room zones. It is also worth noting that the ECO mode is presented in each of the receivers. Both RX-V581 and RX-V485 can be configured using the Setup assistant.
Only the RX-V581 has a Dolby Atmos multichannel audio format support. A surround technology DTS:X is supported only by the RX-V581.