An affordable AV receiver is always a good option to consider, so Yamaha TSR-5810 vs Onkyo TX-8140 comparison definitely makes sense.
A significant difference between the receivers in the number of channels, Yamaha TSR-5810 has 7.2 versus 2.0 for Onkyo TX-8140. Regarding power, then TSR-5810 has such a W/Ohm ratio - 80/8, 145/6 when TX-8140 has a power of 80/8, 110/6. The THD is 0.09% for the TSR-5810 but 0.08% for the TX-8140.
Characteristics of digital to analog converter (DAC) are different, Burr-Brown 192 KHz/24-bit for TSR-5810 and AK4458 384 KHz/32-bit for the TX-8140. Only the TSR-5810 supports Bi-amping feature. 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. Spotify can be used on each receiver. The TSR-5810 can work with the audio stream from Pandora, and the TX-8140 can receive a content from SiriusXM.
Only the Yamaha TSR-5810 has support for High dynamic range (HDR). Only the TSR-5810 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 TSR-5810 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 TSR-5810. The TX-8140 has a built-in phono stage for connecting a vinyl player. An ECO mode is only available for the TSR-5810. Both TSR-5810 and TX-8140 can be configured using the Setup assistant.
Only the TSR-5810 has a Dolby Atmos multichannel audio format support. A surround technology DTS:X is supported only by the TSR-5810.