Having had an opportunity to test Yamaha RX-V4A vs Onkyo TX-NR7100, I’d like to share my impression here to facilitate your choice of a new AV receiver.
The number of channels for receivers is different - 5.2 versus 9.2, respectively, for devices. In terms of power, there are differences, the RX-V4A has such a ratio W/Ohm - 80/6, while the TX-NR7100 has a power of 100/8, 220/6. The value of total harmonic distortion is also different, and for the RX-V4A it is 0.06%, but for the TX-NR7100 it is 0.08%. Each of the compared opponents supports Bi-amping. Both Yamaha RX-V4A and Onkyo TX-NR7100 can transmit an audio signal directly to the amplifier and bypasses any DSP processing.
These units have the same Wi-Fi modules. Each of the receivers has a Bluetooth connector. Both devices can work with such Apple Music services: AirPlay, AirPlay 2. Access to the Spotify service is on each of the competitors. The number of available streaming services varies for receivers, the Yamaha RX-V4A works with Deezer, TIDAL, Pandora, SiriusXM, Qobuz, but the Onkyo TX-NR7100 works with Deezer, TIDAL, Pandora, SiriusXM, Napster, SoundCloud.
The quality of 4K/120Hz signal remains unchanged when transmitting from a source to a TV or projector via HDMI for both receivers. Signaling over HDMI in standby mode can provide the RX-V4A and the TX-NR7100. Each of the devices can increase the resolution of the incoming video signal. Each of the participants of the comparison has a Dolby Vision.
The number of HDMI inputs/outputs varies depending on the receiver, the RX-V4A has 4/1, and the TX-NR7100 has 7/2. HDMI Audio Return Channel is implemented in both devices. HDMI eARC is supported by the RX-V4A and the TX-NR7100. When comparing receivers, it becomes clear that each of the rivals can work with HDMI CEC. RX-V4A and TX-NR7100 support the standard HDCP 2.3. In the presence of a built-in phono stage for connecting a vinyl player only at Onkyo TX-NR7100. For voice control in the RX-V4A is used Amazon Alexa, Google Assistant, Siri, but in the TX-NR7100 is used Amazon Alexa, Google Assistant, Siri, Josh.AI. There is an ECO mode in either AV receiver. The Yamaha RX-V4A and the Onkyo TX-NR7100 can be properly configured using the setup assistant.
A Dolby Atmos multichannel audio format is available only in the TX-NR7100. Only in the TX-NR7100 realized a DTS:X surround technology.