An affordable AV receiver is always a good option to consider, so Denon HEOS AVR vs Onkyo TX-8140 comparison definitely makes sense.
A significant difference between the receivers in the number of channels, Denon HEOS AVR has 5.1 versus 2.0 for Onkyo TX-8140. Regarding power, then HEOS AVR has such a W/Ohm ratio - 50/8, 65/6 when TX-8140 has a power of 80/8, 110/6. The THD is 0.05% for the HEOS AVR but 0.08% 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. None of the competitors supports Auto speaker calibration.
Both models have the ability to connect to the Internet via WI-FI. Rivals from our review have Bluetooth support. Each of these units does not support Apple Music. Spotify can be used on each receiver. The HEOS AVR can work with the audio stream from Deezer, TIDAL, Pandora, Napster, SiriusXM, TuneIn Radio, iHeart Radio, Sound Cloud, and the TX-8140 can receive a content from SiriusXM.
HDR is not available on each model. Only the HEOS AVR 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 HEOS AVR 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 HEOS AVR. The TX-8140 has a built-in phono stage for connecting a vinyl player. An ECO mode is not present in each of the AV receivers. The setup assistant will help you configure Onkyo TX-8140.
None of the rivals equipped with Dolby Atmos multichannel audio decoder. The receivers do not support the surround sound technology DTS:X.