Yamaha RX-V6A vs Yamaha RX-V4A comparison definitely makes sense.
A significant difference between the receivers in the number of channels, Yamaha RX-V6A has 7.2 versus 5.2 for Yamaha RX-V4A. Regarding power, then RX-V6A has such a W/Ohm ratio - 100/8 when RX-V4A has a power of 80/6. The THD is the same and is 0.06%. Both the RX-V6A 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. Deezer, TIDAL, Pandora, SiriusXM, Qobuz - all of these streaming services have found application in each of the models.
Both AV receivers support HDR10 technology (High dynamic range). Compared AV receivers retain the quality of 4K/120Hz 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. The HDR standard - Dolby Vision is supported by these receivers.
The Yamaha RX-V6A has 7/1 HDMI inputs/outputs versus 4/1 HDMI connectors of the Yamaha RX-V4A. 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. Both models support the standard HDCP 2.3. The RX-V6A has 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-V6A and RX-V4A can be configured using the Setup assistant.
Only the RX-V6A has a Dolby Atmos multichannel audio format support. A surround technology DTS:X is supported only by the RX-V6A.