An affordable AV receiver is always a good option to consider, so Yamaha RX-V485BL vs Onkyo TX-8140 comparison definitely makes sense.
A significant difference between the receivers in the number of channels, Yamaha RX-V485BL has 5.1 versus 2.0 for Onkyo TX-8140. Regarding power, then RX-V485BL has such a W/Ohm ratio - 80/6 when TX-8140 has a power of 80/8, 110/6. The THD is 0.09% for the RX-V485BL but 0.08% for the TX-8140.
Characteristics of digital to analog converter (DAC) are different, Burr-Brown 384 KHz/32-bit for RX-V485BL and AK4458 384 KHz/32-bit for the TX-8140. Only the RX-V485BL supports Bi-amping feature. Each of the AV receivers can transmit an audio signal directly to the amplifier and bypasses any DSP processing. Rivals from our review have Bluetooth support. Spotify can be used on each receiver. Only the RX-V485BL provides HDMI signal transmission in standby mode. The RX-V485BL can scale the input HDMI signal, unlike the TX-8140. Dolby Vision technology found support only on the RX-V485BL. Only the RX-V485BL supports HDMI Audio Return Channel (ARC). The HDMI eARC is available only on the RX-V485BL. Of the two receivers in our comparison, HDMI CEC is present in only the RX-V485BL. The TX-8140 has a built-in phono stage for connecting a vinyl player. An ECO mode is only available for the RX-V485BL. Both RX-V485BL 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.