An affordable AV receiver is always a good option to consider, so Yamaha RX-V479BL vs Onkyo TX-8140 comparison definitely makes sense.
A significant difference between the receivers in the number of channels, Yamaha RX-V479BL has 5.1 versus 2.0 for Onkyo TX-8140. Regarding power, then RX-V479BL has such a W/Ohm ratio - 80/8 when TX-8140 has a power of 80/8, 110/6. The THD is 0.09% for the RX-V479BL but 0.08% for the TX-8140.
Characteristics of digital to analog converter (DAC) are different, 192 KHz/24-bit for RX-V479BL and AK4458 384 KHz/32-bit for the TX-8140. None of the models 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. Only the TX-8140 supports Spotify.
HDR is not available on each model. Only the RX-V479BL provides HDMI signal transmission in standby mode. Both competitors are not able to scale the HDMI signal. The HDR standard - Dolby Vision is not supported by these receivers. Only the RX-V479BL supports HDMI Audio Return Channel (ARC). Unfortunately, HDMI eARC is not available on monitored devices. Of the two receivers in our comparison, HDMI CEC is present in only the RX-V479BL. The TX-8140 has a built-in phono stage for connecting a vinyl player. A voice control is not available. An ECO mode is only available for the RX-V479BL. Both RX-V479BL and TX-8140 can be configured using the Setup assistant.
None of the rivals equipped with Dolby Atmos multichannel audio decoder. The receivers do not support the surround sound technology DTS:X.